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Margalho LP, Graça JS, Kamimura BA, Lee SHI, Canales HDS, Chincha AIA, Caturla MYR, Brexó RP, Crucello A, Alvarenga VO, Cruz AG, Oliveira CAF, Sant'Ana AS. Enterotoxigenic Staphylococcus aureus in Brazilian artisanal cheeses: Occurrence, counts, phenotypic and genotypic profiles. Food Microbiol 2024; 121:104531. [PMID: 38637091 DOI: 10.1016/j.fm.2024.104531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 03/24/2024] [Accepted: 04/02/2024] [Indexed: 04/20/2024]
Abstract
The present study aimed to assess the occurrence and counts of Staphylococcus aureus in Brazilian artisanal cheeses (BAC) produced in five regions of Brazil: Coalho and Manteiga (Northeast region); Colonial and Serrano (South); Caipira (Central-West); Marajó (North); and Minas Artisanal cheeses, from Araxá, Campos das Vertentes, Cerrado, Serro and Canastra microregions (Southeast). The resistance to chlorine-based sanitizers, ability to attach to stainless steel surfaces, and antibiogram profile of a large set of S. aureus strains (n = 585) were assessed. Further, a total of 42 isolates were evaluated for the presence of enterotoxigenic genes (sea, seb, sec, sed, see, seg, sei, sej, and ser) and submitted to typing using pulsed-field gel electrophoresis (PFGE). BAC presented high counts of S. aureus (3.4-6.4 log CFU/g), varying from 25 to 62.5%. From the S. aureus strains (n = 585) assessed, 16% could resist 200 ppm of sodium hypochlorite, whereas 87.6% produced strong ability to attach to stainless steel surfaces, corroborating with S. aureus ability to persist and spread in the environment. Furthermore, the relatively high frequency (80.5%) of multidrug-resistant S. aureus and the presence of enterotoxin genes in 92.6% of the strains is of utmost attention. It reveals the lurking threat of SFP that can survive when conditions are favorable. The presence of enterotoxigenic and antimicrobial-resistant strains of S. aureus in cheese constitutes a potential risk to public health. This result calls for better control of cheese contamination sources, and taking hygienic measures is necessary for food safety. More attention should be paid to animal welfare and hygiene practices in some dairy farms during manufacturing to enhance the microbiological quality of traditional cheese products.
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Affiliation(s)
- Larissa P Margalho
- Department of Food Science and Nutrition, Faculty of Food Engineering, University of Campinas, Campinas, SP, Brazil
| | - Juliana S Graça
- Department of Food Science and Nutrition, Faculty of Food Engineering, University of Campinas, Campinas, SP, Brazil
| | - Bruna A Kamimura
- Department of Food Science and Nutrition, Faculty of Food Engineering, University of Campinas, Campinas, SP, Brazil
| | - Sarah H I Lee
- Department of Food Engineering, School of Animal Science and Food Engineering, University of São Paulo, Pirassununga, SP, Brazil
| | - Héctor D S Canales
- Department of Food Science and Nutrition, Faculty of Food Engineering, University of Campinas, Campinas, SP, Brazil
| | - Alexandra I A Chincha
- Department of Food Science and Nutrition, Faculty of Food Engineering, University of Campinas, Campinas, SP, Brazil
| | - Magdevis Y R Caturla
- Department of Food Science and Nutrition, Faculty of Food Engineering, University of Campinas, Campinas, SP, Brazil
| | - Ramon P Brexó
- Department of Food Science and Nutrition, Faculty of Food Engineering, University of Campinas, Campinas, SP, Brazil
| | - Aline Crucello
- Department of Food Science and Nutrition, Faculty of Food Engineering, University of Campinas, Campinas, SP, Brazil
| | - Verônica O Alvarenga
- Department of Food Science and Nutrition, Faculty of Food Engineering, University of Campinas, Campinas, SP, Brazil; Department of Food, Faculty of Pharmacy, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Adriano G Cruz
- Department of Food, Instituto Federal de Educação, Ciência e Tecnologia do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Carlos Augusto F Oliveira
- Department of Food Engineering, School of Animal Science and Food Engineering, University of São Paulo, Pirassununga, SP, Brazil
| | - Anderson S Sant'Ana
- Department of Food Science and Nutrition, Faculty of Food Engineering, University of Campinas, Campinas, SP, Brazil.
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Forouzani‐Moghaddam MJ, Habibi S, Hosseini‐Safa A, Khanaliha K, Mokarinejad R, Akhoundzadeh F, Oshaghi M. Rapid detection of major enterotoxin genes and antibiotic resistance of Staphylococcus aureus isolated from raw milk in the Yazd province, Iran. Vet Med Sci 2024; 10:e1407. [PMID: 38519836 PMCID: PMC10959825 DOI: 10.1002/vms3.1407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 01/22/2024] [Accepted: 02/19/2024] [Indexed: 03/25/2024] Open
Abstract
INTRODUCTION Raw milk is a nutrient-rich food, but it may harbour harmful bacteria, such as enterotoxigenic Staphylococcus aureus (S. aureus), which can cause staphylococcal food poisoning. Antibiotic resistance of S. aureus in raw milk can increase the risk of such infections, particularly among susceptible individuals. OBJECTIVE This study aimed to investigate the prevalence of enterotoxin genes a, d, g, i and j and the antibiotic resistance of S. aureus isolated from raw milk samples. METHODS During a 6-month sampling period, 60 raw milk specimens were obtained from diverse locations in Yazd province, Iran. Antibiogram profiling was conducted via the disc diffusion method. In addition, staphylococcal enterotoxin (SE) genes a, d, g, i, and j were detected through real-time PCR analysis. RESULTS Bacteriological assays confirmed the presence of S. aureus in 11 samples (18.3%). All isolates demonstrated 100% resistance to penicillin G but exhibited sensitivity to vancomycin, while resistance to other antibiotics ranged from 36.4% to 45.5%. The prevalence of enterotoxin genes in these strains showed variable distribution, with sea being the predominant SE (45.5%), followed by sed (36.4%), seg (18.2), sej and sei (9.1% each). CONCLUSIONS This study discovered the presence of multiple enterotoxins in S. aureus strains obtained from raw milk samples. These strains also demonstrated resistance to a variety of antibiotics. Since enterotoxigenic S. aureus is known to cause human food poisoning, monitoring food hygiene practices, especially during raw milk production, is critical.
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Affiliation(s)
| | - Sina Habibi
- Department of Medical Laboratory SciencesFaculty of Allied MedicineIran University of Medical SciencesTehranIran
- Department of Hematology and Blood Banking, Faculty of Allied MedicineIran University of Medical SciencesTehranIran
| | - Ahmad Hosseini‐Safa
- Department of Medical Laboratory SciencesFaculty of Allied MedicineIran University of Medical SciencesTehranIran
| | - Khadijeh Khanaliha
- Research Center of Pediatric Infectious DiseasesInstitute of Immunology and Infectious DiseasesIran University of Medical SciencesTehranIran
| | - Roya Mokarinejad
- Department of Medical Laboratory SciencesFaculty of Allied MedicineIran University of Medical SciencesTehranIran
| | - Fatemeh Akhoundzadeh
- Department of Medical Laboratory SciencesFaculty of Allied MedicineIran University of Medical SciencesTehranIran
| | - Mojgan Oshaghi
- Department of Medical Laboratory SciencesFaculty of Allied MedicineIran University of Medical SciencesTehranIran
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Li H, Li C, Shi C, Sameeh MY, Al-Asmari F, Cui H, Lin L. Transcriptome analysis reveals the inhibitory mechanism of phloretin on virulence expression of Staphylococcus aureus and its application in cooked chicken. Int J Food Microbiol 2024; 415:110647. [PMID: 38422678 DOI: 10.1016/j.ijfoodmicro.2024.110647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 02/10/2024] [Accepted: 02/26/2024] [Indexed: 03/02/2024]
Abstract
Staphylococcus aureus (S. aureus) enterotoxins have aroused great concern to food safety owing to its increased risk of food poisoning. The current research aimed to investigate the anti-virulence mechanisms of phloretin against S. aureus in terms of toxin activity and gene expression. The results indicated that phloretin could effectively inhibit the production of hemolysins and enterotoxins, and its anti-virulence effect was exerted in a concentration-dependent manner. Transcriptome results indicated that phloretin could downregulate the transcription level of majority virulence factors related genes (68 %) of S. aureus, including the quorum sensing-related genes (agrB, agrC, agrA, sspA, splF, splD and others) and bacterial secretion system-related genes (secDF, secY2, and yidC). In addition, it was speculated that phloretin was most likely to bind to the AgrA DNA binding domain, thereby affecting the expression of downstream virulence genes (hla, seb, spa, rot, geh, etc) based on molecular docking. Finally, the application in cooked chicken indicated that phloretin could effectively decrease the content of enterotoxins and improve the storage quality of cooked chicken. These findings not only evidenced the feasible anti-virulence activity of phloretin, but also provided a new strategy to prevent S. aureus food poisoning in cooked meat preservation.
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Affiliation(s)
- Hong Li
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Changzhu Li
- State Key Laboratory of Utilization of Woody Oil Resource, Hunan Academy of Forestry, Changsha 410007, China
| | - Ce Shi
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Manal Y Sameeh
- Department of Chemistry, Al-Leith University College, Umm Al Qura University, Makkah 25100, Saudi Arabia
| | - Fahad Al-Asmari
- Department of Food and Nutrition Sciences, College of Agricultural and Food Sciences, King Faisal University, Al Ahsa 31982, Saudi Arabia
| | - Haiying Cui
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China.
| | - Lin Lin
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China; State Key Laboratory of Utilization of Woody Oil Resource, Hunan Academy of Forestry, Changsha 410007, China.
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Wang C, Defoirdt T, Rajkovic A. The impact of indole and mucin on sporulation, biofilm formation, and enterotoxin production in foodborne Clostridium perfringens. J Appl Microbiol 2024; 135:lxae083. [PMID: 38544331 DOI: 10.1093/jambio/lxae083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 03/13/2024] [Accepted: 03/26/2024] [Indexed: 04/12/2024]
Abstract
AIMS Indole and mucin are compounds found in the host environment as they are produced by the host or by the host-associated microbiota. This study investigated whether indole and mucin impact Clostridium perfringens growth and sporulation, as well as enterotoxin production and biofilm formation. METHODS AND RESULTS There was no impact on growth of Cl. perfringens for up to 400 µM indole and 240 mg/l mucin, and neither indole nor mucin affected sporulation. Reverse-transcriptase qPCR showed that mucin strongly upregulated the expression of Cl. perfringens enterotoxin (up to 121-fold increase), whereas indole had a much more modest effect (2-fold). This was also reflected in increased Cl. perfringens enterotoxin levels in mucin-treated Cl. perfringens (as assessed by a reversed passive latex agglutination assay). Finally, mucin and indole significantly increased biofilm formation of Cl. perfringens, although the effect size was relatively small (less than 1.5 fold). CONCLUSION These results indicate that Cl. perfringens can sense its presence in a host environment by responding to mucin, and thereby markedly increased enterotoxin production.
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Affiliation(s)
- Chao Wang
- Research Unit Food Microbiology and Food Preservation, Department of Food Technology, Safety and Health, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - Tom Defoirdt
- Center for Microbial Ecology and Technology, Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - Andreja Rajkovic
- Research Unit Food Microbiology and Food Preservation, Department of Food Technology, Safety and Health, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
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Shalaby M, Reboud J, Forde T, Zadoks RN, Busin V. Distribution and prevalence of enterotoxigenic Staphylococcus aureus and staphylococcal enterotoxins in raw ruminants' milk: A systematic review. Food Microbiol 2024; 118:104405. [PMID: 38049264 DOI: 10.1016/j.fm.2023.104405] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 10/17/2023] [Accepted: 10/17/2023] [Indexed: 12/06/2023]
Abstract
Enterotoxins produced by Staphylococcus aureus are a common cause of food poisoning, leading to significant gastrointestinal symptoms and even hospitalization. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched three electronic databases for studies on detection of staphylococcal enterotoxins or enterotoxigenic S. aureus in raw ruminant milk. The 128 studies included in this systematic review showed a worldwide distribution of studies on staphylococcal enterotoxins and enterotoxigenic S. aureus, with an increase in the number from 1980 to 2021, a shift in detection methods from enterotoxins to enterotoxin genes, and a preponderance of studies from Europe and South America. Most studies focused on milk from individual animals with mastitis, especially cattle. Based on 24 studies, the within-herd prevalence of enterotoxigenic S. aureus in raw milk samples was 11.6%. Many studies failed to report the health status of sampled animals, or the numerator and denominator data needed for prevalence calculation. Cultural and legislative differences, economic status, diagnostic capabilities, and public awareness are all likely factors contributing to the observed distribution of studies. Our review highlighted a significant gap in quality and completeness of data reporting, which limits full assessment of prevalence and distribution of hazards posed by raw milk.
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Affiliation(s)
- Maha Shalaby
- School of Biodiversity, One Health & Veterinary Medicine, University of Glasgow, Glasgow, United Kingdom; James Watt School of Engineering, University of Glasgow, Glasgow, United Kingdom; Food Control Department, Faculty of Veterinary Medicine, Kafrelsheikh University, Kafr-El-Sheikh, 33516, Egypt.
| | - Julien Reboud
- James Watt School of Engineering, University of Glasgow, Glasgow, United Kingdom
| | - Taya Forde
- School of Biodiversity, One Health & Veterinary Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Ruth N Zadoks
- School of Biodiversity, One Health & Veterinary Medicine, University of Glasgow, Glasgow, United Kingdom; Sydney School of Veterinary Science, Faculty of Science, The University of Sydney, NSW, 2006, Australia
| | - Valentina Busin
- School of Biodiversity, One Health & Veterinary Medicine, University of Glasgow, Glasgow, United Kingdom.
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Suzuki Y, Ishitsuka T, Takagi M, Sasaki Y, Kakuda T, Kobayashi K, Kubota H, Ono HK, Kabeya H, Irie T, Andoh M, Asakura H, Takai S. Isolation and genetic characterization of Staphylococcus aureus from wild animal feces and game meats. Folia Microbiol (Praha) 2024; 69:347-360. [PMID: 37405631 DOI: 10.1007/s12223-023-01071-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 06/12/2023] [Indexed: 07/06/2023]
Abstract
The populations of Japanese deer and boar have increased dramatically and have a serious impact on farming and mountain villages. Although the Japanese government promotes the use of captured wild animals, game meat is not subject to sanitary control considering that it is not subject to meat inspection or quality control. Here, we have attempted to isolate Staphylococcus aureus, a typical foodborne pathogen, as a part of an investigation of contamination in the meats of wild animals and their processing stages. We examined 390 samples of deer feces, 117 samples of wild boar feces, and 75 samples of disemboweled deer meat for isolation of S. aureus; ultimately, 30 (positive rate: 7.7%), 2 (1.7%), and 21 (28.0%) strains were isolated, respectively, from the samples. The genome sequences of these isolates were analyzed and were subjected to multilocus sequence typing. We identified 12 new sequence types (STs) and a dominant population of S. aureus with a characteristic genetic background in wild animals, namely, the ST groups derived from CC121 (number of strains = 39). These strains did not harbor the enterotoxin gene or only harbored egc-related enterotoxin, which is of low involvement in Staphylococcal food poisoning. However, one ST2449 strain, which produces causative enterotoxins, was isolated from a deer's feces. Since there are several common STs isolated from feces and dismembered meat and because fecal contamination during dismemberment is suspected, continuous monitoring and guidance for improving sanitary management conditions during processing and handling of the meat are highly warranted with immediate effect.
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Affiliation(s)
- Yasunori Suzuki
- Laboratory of Animal Hygiene, Kitasato University School of Veterinary Medicine, Higashi 23-35-1, Towada, Aomori, 034-8628, Japan.
| | - Toko Ishitsuka
- Laboratory of Animal Hygiene, Kitasato University School of Veterinary Medicine, Higashi 23-35-1, Towada, Aomori, 034-8628, Japan
| | - Miu Takagi
- Laboratory of Animal Hygiene, Kitasato University School of Veterinary Medicine, Higashi 23-35-1, Towada, Aomori, 034-8628, Japan
| | - Yukako Sasaki
- Laboratory of Animal Hygiene, Kitasato University School of Veterinary Medicine, Higashi 23-35-1, Towada, Aomori, 034-8628, Japan
| | - Tsutomu Kakuda
- Laboratory of Animal Hygiene, Kitasato University School of Veterinary Medicine, Higashi 23-35-1, Towada, Aomori, 034-8628, Japan
| | - Kai Kobayashi
- Department of Microbiology, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunin-Cho, Shinjuku-Ku, Tokyo, 169-0073, Japan
| | - Hiroaki Kubota
- Department of Microbiology, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunin-Cho, Shinjuku-Ku, Tokyo, 169-0073, Japan
| | - Hisaya K Ono
- Laboratory of Zoonoses, Kitasato University School of Veterinary Medicine, Higashi 23-35-1, Towada, Aomori, 034-8628, Japan
| | - Hidenori Kabeya
- Laboratory of Veterinary Food Hygiene, Department of Veterinary Medicine, College of Bioresource Sciences, Nihon University, 1866 Kameino, Fujisawa, Kanagawa, 252-0880, Japan
| | - Takao Irie
- Laboratory of Veterinary Parasitic Diseases, Department of Veterinary Sciences, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen-Kibanadai-Nishi, Miyazaki, 889-2192, Japan
| | - Masako Andoh
- Department of Pathogenetic and Preventive Veterinary Science, Joint Faculty of Veterinary Medicine, Kagoshima University, 1-21-24 Korimoto, Kagoshima, Kagoshima, 890-0065, Japan
| | - Hiroshi Asakura
- Division of Biomedical Food Research, National Institute of Health Sciences, 3-25-26, Tonomachi, Kawasaki-Ku, Kawasaki, Kanagawa, 210-9501, Japan
| | - Shinji Takai
- Laboratory of Animal Hygiene, Kitasato University School of Veterinary Medicine, Higashi 23-35-1, Towada, Aomori, 034-8628, Japan
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Pajuelo MJ, Noazin S, Cabrera L, Toledo A, Velagic M, Arias L, Ochoa M, Moulton LH, Saito M, Gilman RH, Chakraborty S. Epidemiology of enterotoxigenic Escherichia coli and impact on the growth of children in the first two years of life in Lima, Peru. Front Public Health 2024; 12:1332319. [PMID: 38584932 PMCID: PMC10995271 DOI: 10.3389/fpubh.2024.1332319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 03/11/2024] [Indexed: 04/09/2024] Open
Abstract
Background Enterotoxigenic E. coli (ETEC) is a leading cause of diarrheal morbidity and mortality in children, although the data on disease burden, epidemiology, and impact on health at the community level are limited. Methods In a longitudinal birth cohort study of 345 children followed until 24 months of age in Lima, Peru, we measured ETEC burden in diarrheal and non-diarrheal samples using quantitative PCR (LT, STh, and STp toxin genes), studied epidemiology and measured anthropometry in children. Results About 70% of children suffered from one or more ETEC diarrhea episodes. Overall, the ETEC incidence rate (IR) was 73 per 100 child-years. ETEC infections began early after birth causing 10% (8.9-11.1) ETEC-attributable diarrheal burden at the population level (PAF) in neonates and most of the infections (58%) were attributed to ST-ETEC [PAF 7.9% (1.9-13.5)] and LT + ST-ETEC (29%) of which all the episodes were associated with diarrhea. ETEC infections increased with age, peaking at 17% PAF (4.6-27.7%; p = 0.026) at 21 to 24 months. ST-ETEC was the most prevalent type (IR 32.1) with frequent serial infections in a child. The common colonization factors in ETEC diarrhea cases were CFA/I, CS12, CS21, CS3, and CS6, while in asymptomatic ETEC cases were CS12, CS6 and CS21. Only few (5.7%) children had repeated infections with the same combination of ETEC toxin(s) and CFs, suggested genotype-specific immunity from each infection. For an average ETEC diarrhea episode of 5 days, reductions of 0.060 weight-for-length z-score (0.007 to 0.114; p = 0.027) and 0.061 weight-for-age z-score (0.015 to 0.108; p = 0.009) were noted in the following 30 days. Conclusion This study showed that ETEC is a significant pathogen in Peruvian children who experience serial infections with multiple age-specific pathotypes, resulting in transitory growth impairment.
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Affiliation(s)
- Monica J. Pajuelo
- Laboratorio Microbiología Molecular – Laboratorios de Investigación y Desarrollo, Facultad de Ciencias e Ingeniería, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Sassan Noazin
- Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | | | - Angie Toledo
- Laboratorio Microbiología Molecular – Laboratorios de Investigación y Desarrollo, Facultad de Ciencias e Ingeniería, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Mirza Velagic
- Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | - Lucero Arias
- Laboratorio Microbiología Molecular – Laboratorios de Investigación y Desarrollo, Facultad de Ciencias e Ingeniería, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Mayra Ochoa
- Laboratorio Microbiología Molecular – Laboratorios de Investigación y Desarrollo, Facultad de Ciencias e Ingeniería, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Lawrence H. Moulton
- Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | - Mayuko Saito
- Department of Virology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Robert H. Gilman
- Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | - Subhra Chakraborty
- Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
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Sato'o Y, Hisatsune J, Aziz F, Tatsukawa N, Shibata-Nakagawa M, Ono HK, Naito I, Omoe K, Sugai M. Coordination of prophage and global regulator leads to high enterotoxin production in staphylococcal food poisoning-associated lineage. Microbiol Spectr 2024; 12:e0292723. [PMID: 38319074 PMCID: PMC10913437 DOI: 10.1128/spectrum.02927-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 01/05/2024] [Indexed: 02/07/2024] Open
Abstract
Staphylococcus species in food produce Staphylococcal enterotoxins (SEs) that cause Staphylococcal food poisoning (SFP). More than 20 SE types have been reported, among which Staphylococcal enterotoxin A (SEA) has been recognized as one of the most important SEs associated with SFP. However, the regulatory mechanisms underlying its production remain unclear. Previously, we identified a major SFP clone in Japan, CC81 subtype-1, which exhibits high SEA production. In this study, we attempted to identify the factors contributing to this phenomenon. Thus, we demonstrated that the attenuation of the activity of endogenous regulator, Staphylococcal accessory regulator S (SarS), and the lysogenization of a high SEA-producing phage contributed to this phenomenon in CC81 subtype-1. Furthermore, our results indicated that SarS could directly bind to the promoter upstream of the sea gene and suppress SEA expression; this low SarS repression activity was identified as one of the reasons for the high SEA production observed. Therefore, we revealed that both exogenous and endogenous factors may probably contribute to the high SEA production. Our results confirmed that SE production is a fundamental and critical factor in SFP and clarified the associated production mechanism while enhancing our understanding as to why a specific clone frequently causes SFP. IMPORTANCE The importance of this study lies in its unveiling of a molecular regulatory mechanism associated with the most important food poisoning toxin and the evolution of Staphylococcal food poisoning (SFP)-associated clone. SFP is primarily caused by Staphylococcus aureus, with Staphylococcal enterotoxin A (SEA) being commonly involved in many cases. Thus, SEA has been recognized as a major toxin type. However, despite almost a century since its discovery, the complete mechanism of SEA production is as yet unknown. In this study, we analyzed an SEA-producing SFP clone isolated in East Asia and discovered that this strain, besides acquiring the high SEA-producing phage, exhibits remarkably high SEA production due to the low activity of SarS, an intrinsic regulatory factor. This is the first report documenting the evolution of the SFP clone through the coordinated action of exogenous mobile genetic factors and endogenous regulators on this notorious toxin.
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Affiliation(s)
- Yusuke Sato'o
- Department of Bacteriology, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima, Japan
| | - Junzo Hisatsune
- Department of Bacteriology, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima, Japan
- Antimicrobial Resistance Research Center, National Institute of Infectious Diseases (NIID), Tokyo, Japan
| | - Fatkhanuddin Aziz
- Department of Bacteriology, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima, Japan
| | - Nobuyuki Tatsukawa
- Department of Bacteriology, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima, Japan
| | - Mari Shibata-Nakagawa
- Department of Veterinary Medicine, Faculty of Agriculture, Iwate University, Morioka city, Japan
| | - Hisaya K. Ono
- Department of Veterinary Medicine, Faculty of Agriculture, Iwate University, Morioka city, Japan
- Laboratory of Zoonoses, Kitasato University School of Veterinary Medicine, Towada city, Japan
| | - Ikunori Naito
- Department of Veterinary Medicine, Faculty of Agriculture, Iwate University, Morioka city, Japan
| | - Katsuhiko Omoe
- Department of Veterinary Medicine, Faculty of Agriculture, Iwate University, Morioka city, Japan
| | - Motoyuki Sugai
- Department of Bacteriology, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima, Japan
- Antimicrobial Resistance Research Center, National Institute of Infectious Diseases (NIID), Tokyo, Japan
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Kakita T, Lee K, Morita M, Okuno M, Kyan H, Okano S, Maeshiro N, Ishizu M, Kudeken T, Taira H, Teruya M, Ogura Y, Akeda Y, Ohnishi M. Isolation and whole-genome sequencing analysis of Escherichia fergusonii harboring a heat-labile enterotoxin gene from retail chicken meat in Okinawa, Japan. Microbiol Immunol 2024; 68:115-121. [PMID: 38244192 DOI: 10.1111/1348-0421.13115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 12/02/2023] [Accepted: 01/04/2024] [Indexed: 01/22/2024]
Abstract
This study aimed to reveal the prevalence of heat-labile enterotoxin (LT) gene-positive Escherichia fergusonii in retail chicken meat and genetically characterize these strains. E. fergusonii harboring LT gene was isolated from 6 out of 60 (10%) retail chicken samples in Okinawa, Japan. Whole-genome sequencing analysis revealed that LT gene-positive E. fergusonii from chicken meat and feces contain an IncFII plasmid harboring elt1AB, and suggested to spread clonally to retail chicken through fecal contamination. Additionally, it was found that these strains harbor multidrug-resistant genes on their plasmids. Their pathogenicity and continuous monitoring are required for confirmation.
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Affiliation(s)
- Tetsuya Kakita
- Research Center for Infectious Disease, Okinawa Prefectural Institute of Health and Environment, Okinawa, Japan
| | - Kenichi Lee
- Department of Bacteriology I, National Institute of Infectious Disease, Tokyo, Japan
| | - Masatomo Morita
- Department of Bacteriology I, National Institute of Infectious Disease, Tokyo, Japan
| | - Miki Okuno
- Division of Microbiology, Department of Infectious Medicine, Kurume University School of Medicine, Fukuoka, Japan
| | - Hisako Kyan
- Research Center for Infectious Disease, Okinawa Prefectural Institute of Health and Environment, Okinawa, Japan
| | - Sho Okano
- Research Center for Infectious Disease, Okinawa Prefectural Institute of Health and Environment, Okinawa, Japan
| | - Noriyuki Maeshiro
- Research Center for Infectious Disease, Okinawa Prefectural Institute of Health and Environment, Okinawa, Japan
| | - Momoko Ishizu
- Research Center for Infectious Disease, Okinawa Prefectural Institute of Health and Environment, Okinawa, Japan
| | - Tsuyoshi Kudeken
- Research Center for Infectious Disease, Okinawa Prefectural Institute of Health and Environment, Okinawa, Japan
| | - Haruno Taira
- Research Center for Infectious Disease, Okinawa Prefectural Institute of Health and Environment, Okinawa, Japan
| | - Morimi Teruya
- Research Center for Infectious Disease, Okinawa Prefectural Institute of Health and Environment, Okinawa, Japan
| | - Yoshitoshi Ogura
- Division of Microbiology, Department of Infectious Medicine, Kurume University School of Medicine, Fukuoka, Japan
| | - Yukihiro Akeda
- Department of Bacteriology I, National Institute of Infectious Disease, Tokyo, Japan
| | - Makoto Ohnishi
- Research Center for Infectious Disease, Okinawa Prefectural Institute of Health and Environment, Okinawa, Japan
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10
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Ghosh S, Erickson D, Chua MJ, Collins J, Jala VR. The microbial metabolite urolithin A reduces Clostridioides difficile toxin expression and toxin-induced epithelial damage. mSystems 2024; 9:e0125523. [PMID: 38193707 PMCID: PMC10878087 DOI: 10.1128/msystems.01255-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Accepted: 12/04/2023] [Indexed: 01/10/2024] Open
Abstract
Clostridioides difficile is a Gram-positive, anaerobic, spore-forming bacterium responsible for antibiotic-associated pseudomembranous colitis. Clostridioides difficile infection (CDI) symptoms can range from diarrhea to life-threatening colon damage. Toxins produced by C. difficile (TcdA and TcdB) cause intestinal epithelial injury and lead to severe gut barrier dysfunction, stem cell damage, and impaired regeneration of the gut epithelium. Current treatment options for intestinal repair are limited. In this study, we demonstrate that treatment with the microbial metabolite urolithin A (UroA) attenuates CDI-induced adverse effects on the colon epithelium in a preclinical model of CDI-induced colitis. Moreover, our analysis suggests that UroA treatment protects against C. difficile-induced inflammation, disruption of gut barrier integrity, and intestinal tight junction proteins in the colon of CDI mice. Importantly, UroA treatment significantly reduced the expression and release of toxins from C. difficile without inducing bacterial cell death. These results indicate the direct regulatory effects of UroA on bacterial gene regulation. Overall, our findings reveal a novel aspect of UroA activity, as it appears to act at both the bacterial and host levels to protect against CDI-induced colitis pathogenesis. This research sheds light on a promising avenue for the development of novel treatments for C. difficile infection.IMPORTANCETherapy for Clostridioides difficile infections includes the use of antibiotics, immunosuppressors, and fecal microbiota transplantation. However, these treatments have several drawbacks, including the loss of colonization resistance, the promotion of autoimmune disorders, and the potential for unknown pathogens in donor samples. To date, the potential benefits of microbial metabolites in CDI-induced colitis have not been fully investigated. Here, we report for the first time that the microbial metabolite urolithin A has the potential to block toxin production from C. difficile and enhance gut barrier function to mitigate CDI-induced colitis.
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Affiliation(s)
- Sweta Ghosh
- Department of Microbiology and Immunology, University of Louisville, Louisville, Kentucky, USA
- UofL-Brown Cancer Center, Louisville, Kentucky, USA
| | - Daniel Erickson
- Department of Microbiology and Immunology, University of Louisville, Louisville, Kentucky, USA
| | - Michelle J. Chua
- Department of Microbiology and Immunology, University of Louisville, Louisville, Kentucky, USA
| | - James Collins
- Department of Microbiology and Immunology, University of Louisville, Louisville, Kentucky, USA
- Center for Predictive Medicine, University of Louisville, Louisville, Kentucky, USA
- Center for Microbiomics, Inflammation and Pathogenicity, University of Louisville, Louisville, Kentucky, USA
| | - Venkatakrishna Rao Jala
- Department of Microbiology and Immunology, University of Louisville, Louisville, Kentucky, USA
- UofL-Brown Cancer Center, Louisville, Kentucky, USA
- Center for Microbiomics, Inflammation and Pathogenicity, University of Louisville, Louisville, Kentucky, USA
- Center for Integrative Environmental Health Sciences, University of Louisville, Louisville, Kentucky, USA
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11
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Algammal AM, Eid HM, Alghamdi S, Ghabban H, Alatawy R, Almanzalawi EA, Alqahtani TM, Elfouly SG, Mohammed GM, Hetta HF, El-Tarabili RM. Meat and meat products as potential sources of emerging MDR Bacillus cereus: groEL gene sequencing, toxigenic and antimicrobial resistance. BMC Microbiol 2024; 24:50. [PMID: 38326741 PMCID: PMC10848520 DOI: 10.1186/s12866-024-03204-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 01/24/2024] [Indexed: 02/09/2024] Open
Abstract
BACKGROUND Bacillus cereus is implicated in severe foodborne infection in humans. This study intended to assess the occurrence, groEL gene sequencing, biofilm production, and resistance profiles of emerged multidrug resistant (MDR) B. cereus in meat and meat product samples. Moreover, this work highlights the virulence and toxigenic genes (hblABCD complex, nheABC complex, cytK, ces, and pc-plc) and antimicrobial resistance genes (bla1, tetA, bla2, tetB, and ermA). METHODS Consequently, 200 samples (sausage, minced meat, luncheon, beef meat, and liver; n = 40 for each) were indiscriminately collected from commercial supermarkets in Port Said Province, Egypt, from March to May 2021. Subsequently, food samples were bacteriologically examined. The obtained isolates were tested for groEL gene sequence analysis, antibiotic susceptibility, biofilm production, and PCR screening of toxigenic and resistance genes. RESULTS The overall prevalence of B. cereus among the inspected food samples was 21%, where the highest predominance was detected in minced meat (42.5%), followed by beef meat (30%). The phylogenetic analysis of the groEL gene exposed that the examined B. cereus strain disclosed a notable genetic identity with other strains from the USA and China. Moreover, the obtained B. cereus strains revealed β-hemolytic activity, and 88.1% of the recovered strains tested positive for biofilm production. PCR evidenced that the obtained B. cereus strains usually inherited the nhe complex genes (nheA and nheC: 100%, and nheB: 83.3%), followed by cytK (76.2%), hbl complex (hblC and hblD: 59.5%, hblB: 16.6%, and hblA: 11.9%), ces (54.7%), and pc-plc (30.9%) virulence genes. Likewise, 42.9% of the examined B. cereus strains were MDR to six antimicrobial classes and encoded bla1, bla2, ermA, and tetA genes. CONCLUSION In summary, this study highlights the presence of MDR B. cereus in meat and meat products, posing a significant public health risk. The contamination by B. cereus is common in minced meat and beef meat. The molecular assay is a reliable fundamental tool for screening emerging MDR B. cereus strains in meat and meat products.
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Affiliation(s)
- Abdelazeem M Algammal
- Department of Bacteriology, Immunology and Mycology, Faculty of Veterinary Medicine, Suez Canal University, Ismailia, 41522, Egypt.
| | - Hamza M Eid
- Department of Microbiology, Faculty of Veterinary Medicine, Ain Shams University, Cairo, 11566, Egypt
| | - Saad Alghamdi
- Department of Clinical Laboratory Sciences, Faculty of Applied Medical Sciences, Umm Al-Qura University, Makkah, 24381, Saudi Arabia
| | - Hanaa Ghabban
- Department of Biology, Faculty of Science, University of Tabuk, Tabuk, 71491, Saudi Arabia
| | - Roba Alatawy
- Medical Microbiology Department, School of Medicine, University of Tabuk, Tabuk, 71491, Saudi Arabia
| | - Enas A Almanzalawi
- Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| | - Tahani M Alqahtani
- Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| | - Sabreen G Elfouly
- Department of Bacteriology, Animal Health Research Institute, Port-Said branch, Port Said, 42511, Egypt
| | - Gihan M Mohammed
- Department of Bacteriology, Animal Health Research Institute, Port-Said branch, Port Said, 42511, Egypt
| | - Helal F Hetta
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut, 71515, Egypt
| | - Reham M El-Tarabili
- Department of Bacteriology, Immunology and Mycology, Faculty of Veterinary Medicine, Suez Canal University, Ismailia, 41522, Egypt
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12
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Etter D, Biggel M, Greutmann M, Cernela N, Johler S. New insights into Bacillus cytotoxicus sources, screening, toxicity, and persistence in food production facilities. Food Microbiol 2024; 117:104399. [PMID: 37919007 DOI: 10.1016/j.fm.2023.104399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 10/03/2023] [Accepted: 10/06/2023] [Indexed: 11/04/2023]
Abstract
Bacillus cytotoxicus is a thermotolerant member of the Bacillus cereus group. It has been linked to rare, but at times fatal cases of diarrheal disease and might be missed at routine diagnostic screening temperatures commonly used for the B. cereus group. The pathogen is mostly found on dehydrated foods containing potato starch or insects. How it enters the food chain or whether it persists in food producing environments is largely unknown. Increased consumption of insects and convenience foods in Europe and the lack of information on the persistence of B. cytotoxicus in food environments and its virulence demand for further characterization. In this study, we aimed to obtain a better understanding of i) the food sources of B. cytotoxicus, ii) screening temperatures needed for its isolation from food matrices, iii) cytotoxicity of the organism, and iv) its ecological niche and potential epidemiological links. To this end, 112 food samples were collected, with a focus on foods exhibiting low water activity. The samples were screened for B. cytotoxicus at 42 °C and at 50 °C. Presumptive isolates were characterized by cytK-1 toxin gene PCR for differentiation of B. cytotoxicus from other B. cereus group members. Vero cell cytotoxicity assays were performed, and selected isolates were sequenced. Our results show that screening at 42 °C might be insufficient for detecting B. cytotoxicus in foods that harbor other less thermophilic Bacillus species. When screening at 50 °C, B. cytotoxicus was detected in 23% of the food samples (n = 26 isolates). The highest prevalence was detected in mashed potato products (82%) and potato flakes (67%). In contrast, a wide range of products not containing any potato ingredients did not yield B. cytotoxicus isolates. All B. cytotoxicus isolates exhibited either low or no detectable cytotoxicity. WGS analysis revealed that a highly toxic isolate is closely related to the French outbreak strain NVH 391-98. In addition, we could show that two isolates sampled 5 years apart from the same production facility only differed by seven SNPs, making it likely that B. cytotoxicus is able to persist in production facilities over a long time. Interestingly, the reoccurring strain possessed an additional plasmid and did not show cytotoxic potential when re-isolated after 5 years.
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Affiliation(s)
- Danai Etter
- Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Michael Biggel
- Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Mariella Greutmann
- Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Nicole Cernela
- Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Sophia Johler
- Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland.
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13
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Jurado A, Fernández L, Rodríguez A, García P. Prevalence of virulence- and antibiotic resistance-associated genotypes and phenotypes in Staphylococcus aureus strains from the food sector compared to clinical and cow mastitis isolates. Front Cell Infect Microbiol 2024; 14:1327131. [PMID: 38348375 PMCID: PMC10859521 DOI: 10.3389/fcimb.2024.1327131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 01/12/2024] [Indexed: 02/15/2024] Open
Abstract
Background Infections by the pathogen Staphylococcus aureus currently represent one of the most serious threats to human health worldwide, especially due to the production of enterotoxins and the ability to form biofilms. These structures and the acquisition of antibiotic resistance limit the action of antibiotics and disinfectants used to combat this microorganism in the industry and the clinic. Methods This work reports a comparative phenotypic and genotypic study of 18 S. aureus strains from different origins: clinical samples, milk from mastitic cows and food industry surfaces, most of which were isolated in Northern Spain. Results Genetically, the strains were very diverse but, in most cases, a closer proximity was observed for those from the same source. Notably, the average number of virulence genes was not significantly different in strains from the food sector. Of the 18 strains, 10 coded for at least one enterotoxin, and four of them carried 6 or 7 enterotoxin genes. The latter were all veterinary or clinical isolates. Most strains carried prophages, plasmids and/or pathogenicity islands. Regarding antibiotic resistance, although phenotypically all strains showed resistance to at least one antibiotic, resistance genes were only identified in 44.5% of strains, being mastitis isolates those with the lowest prevalence. Virulence-related phenotypic properties such as haemolytic activity, staphyloxanthin production, biofilm-forming capacity and spreading ability were widely distributed amongst the isolates. Conclusions Our results indicate that production of virulence factors, antibiotic resistance and biofilm formation can be found in S. aureus isolates from diverse environments, including the food industry, although some of these traits are more prevalent in strains isolated from infections in cows or humans. This emphasizes on the importance of monitoring the spread of these determinants not only in samples from the clinical environment, but also along the food chain, a strategy that falls under the prism of a one-health approach.
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Affiliation(s)
- Andrea Jurado
- Department of Technology and Biotechnology, Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Asturias, Spain
- DairySafe Group. Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Oviedo, Spain
| | - Lucía Fernández
- Department of Technology and Biotechnology, Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Asturias, Spain
- DairySafe Group. Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Oviedo, Spain
| | - Ana Rodríguez
- Department of Technology and Biotechnology, Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Asturias, Spain
- DairySafe Group. Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Oviedo, Spain
| | - Pilar García
- Department of Technology and Biotechnology, Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Asturias, Spain
- DairySafe Group. Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Oviedo, Spain
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Sapa D, Brosse A, Coullon H, Péan de Ponfilly G, Candela T, Le Monnier A. A Streamlined Method to Obtain Biologically Active TcdA and TcdB Toxins from Clostridioides difficile. Toxins (Basel) 2024; 16:38. [PMID: 38251254 PMCID: PMC10821508 DOI: 10.3390/toxins16010038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 12/15/2023] [Accepted: 12/30/2023] [Indexed: 01/23/2024] Open
Abstract
The major virulence factors of Clostridioides difficile (C. difficile) are enterotoxins A (TcdA) and B (TcdB). The study of toxins is a crucial step in exploring the virulence of this pathogen. Currently, the toxin purification process is either laborious and time-consuming in C. difficile or performed in heterologous hosts. Therefore, we propose a streamlined method to obtain functional toxins in C. difficile. Two C. difficile strains were generated, each harboring a sequence encoding a His-tag at the 3' end of C. difficile 630∆erm tcdA or tcdB genes. Each toxin gene is expressed using the Ptet promoter, which is inducible by anhydro-tetracycline. The obtained purification yields were 0.28 mg and 0.1 mg per liter for rTcdA and rTcdB, respectively. In this study, we successfully developed a simple routine method that allows the production and purification of biologically active rTcdA and rTcdB toxins with similar activities compared to native toxins.
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Affiliation(s)
- Diane Sapa
- Micalis Institute, Université Paris-Saclay, INRAE, AgroParisTech, 78350 Jouy-en-Josas, France; (D.S.); (H.C.); (G.P.d.P.); (T.C.); (A.L.M.)
| | - Anaïs Brosse
- Micalis Institute, Université Paris-Saclay, INRAE, AgroParisTech, 78350 Jouy-en-Josas, France; (D.S.); (H.C.); (G.P.d.P.); (T.C.); (A.L.M.)
| | - Héloïse Coullon
- Micalis Institute, Université Paris-Saclay, INRAE, AgroParisTech, 78350 Jouy-en-Josas, France; (D.S.); (H.C.); (G.P.d.P.); (T.C.); (A.L.M.)
| | - Gauthier Péan de Ponfilly
- Micalis Institute, Université Paris-Saclay, INRAE, AgroParisTech, 78350 Jouy-en-Josas, France; (D.S.); (H.C.); (G.P.d.P.); (T.C.); (A.L.M.)
- Service de Microbiologie Clinique, GH Paris Saint-Joseph, 75674 Paris, France
| | - Thomas Candela
- Micalis Institute, Université Paris-Saclay, INRAE, AgroParisTech, 78350 Jouy-en-Josas, France; (D.S.); (H.C.); (G.P.d.P.); (T.C.); (A.L.M.)
| | - Alban Le Monnier
- Micalis Institute, Université Paris-Saclay, INRAE, AgroParisTech, 78350 Jouy-en-Josas, France; (D.S.); (H.C.); (G.P.d.P.); (T.C.); (A.L.M.)
- Service de Microbiologie Clinique, GH Paris Saint-Joseph, 75674 Paris, France
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15
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Zhang P, Zhang Y, Ruan F, Chang G, Lü Z, Tian L, Ji H, Zhou T, Wang X. Genotypic diversity of staphylococcal enterotoxin B gene (seb) and its association with molecular characterization and antimicrobial resistance of Staphylococcus aureus from retail food. Int J Food Microbiol 2024; 408:110444. [PMID: 37862853 DOI: 10.1016/j.ijfoodmicro.2023.110444] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Revised: 09/19/2023] [Accepted: 10/09/2023] [Indexed: 10/22/2023]
Abstract
To investigate the expression pattern of staphylococcal enterotoxin B (SEB) in food and the genotypic diversity of SEB-encoding gene in association with molecular characteristics and antimicrobial resistance of S. aureus, 498 isolates from retail food were screened for seb gene and detected for SEB production in S. aureus. In addition, the seb nucleotide sequences, virulence genes, resistance genes, antimicrobial susceptibility and molecular characteristics of S. aureus were examined. A total of 45 (9.0 %) seb-positive S. aureus strains were identified, all of which expressed SEB. The detection rate of SEB-production strains was significantly higher from dairy-related sources than those from other sources (P < 0.05). In vitro simulations showed that S. aureus could grow and express SEB in both milk and pork, with SEB expression exceeding 20 ng/g after 1 day of storage at room temperature. There were 2 distinct SEB genotyping (SEB1 and SEB2) in the SEB amino acid sequences of the 45 isolates, including 4 amino acid differences (Ala-13Val, Ser14Ala, Asn192Ser, and Met222Leu). There was no significant difference (P > 0.05) in SEB production between SEB1 and SEB2 genotyping strains. Based on MLST clustering analysis, the same molecular type strains were found to have the same SEB genotyping, virulence gene profile, resistance gene profile and drug resistance profile. Among them, the dominant molecular types of SEB1 and SEB2 strains were CC1-ST188-t189 and CC59-ST59-t437, respectively. Compared to the CC1-ST188-t189 clonal strain, the CC59-ST59-t437 clonal strain carried a higher number of virulence and resistance genes and exhibited a broader resistance profile. Therefore, understanding the characteristics of the strains and their expression patterns in food can be effective in preventing food poisoning incidents.
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Affiliation(s)
- Pengfei Zhang
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Yao Zhang
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Fuqian Ruan
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Guanhong Chang
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Zexun Lü
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Lei Tian
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Hua Ji
- School of Food Science and Technology, Shihezi University, Shihezi 832003, China
| | - Ting Zhou
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Xin Wang
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China.
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16
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Elshazely RMY, Amer IH, Aal SFAAE, Aal SFAAE, Tahoun ABMB. Antibacterial effect of Moringa oleifera on Staphylococcus aureus and Pseudomonas aeruginosa isolated from raw milk and some dairy products with special reference to biofilm gene expression. Open Vet J 2024; 14:164-175. [PMID: 38633171 PMCID: PMC11018401 DOI: 10.5455/ovj.2024.v14.i1.15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Accepted: 12/15/2023] [Indexed: 04/19/2024] Open
Abstract
Background Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus) are well defined as food poisoning pathogens that are highly resistant and need continuous studies. Aim The purpose of the work was to examine phenotypic and genotypic characteristics of both P. aeruginosa and S. aureus, and treatment trials with medicinal plants. Methods Samples were examined for isolation of P. aeruginosa and S. aureus on selective media followed by biochemical confirmation, biofilm formation, genes detection, and expression of P. aeruginosa pslA biofilm gene was performed by quantitative real-time polymerase chain reaction after treatment with 0.312 mg/ml Moringa oleifera aqueous extract as a minimum inhibitory concentration. Results The highest isolation rate of P. aeruginosa was 20% from both raw milk and Kariesh cheese, followed by 16% and 12% from ice cream and processed cheese, respectively, while the highest isolation rate of S. aureus was 36% from raw milk followed by 28% in ice cream and 16% in both Kariesh cheese and processed cheese. 30% of P. aeruginosa isolates were biofilm producers, while only 21% of S. aureus isolates were able to produce biofilm. The P. aeruginosa isolates harbor virulence-associated genes nan1, exoS, toxA, and pslA at 100%, 80%, 40%, and 40%, respectively. Staphylococcus aureus SEs genes were examined in S. aureus strains, where SEA and SEB genes were detected with 60%, but no isolate harbored SEC, SED, or SEE. The significant fold change of P. aeruginosa pslA expression was 0.40332 after treatment with M. oleifera aqueous extract. Conclusion Pseudomonas aeruginosa and S. aureus harbor dangerous virulence genes that cause food poisoning, but M. oleifera extract could minimize their action.
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Affiliation(s)
| | - Ibrahim H. Amer
- Department of Food Hygiene, Safety and Technology, Faculty of Veterinary Medicine, Zagazig University, Zagazig City, Egypt
| | - Salah F. A. Abd-El Aal
- Department of Food Hygiene, Safety and Technology, Faculty of Veterinary Medicine, Zagazig University, Zagazig City, Egypt
| | - Salah F. A. Abd-El Aal
- Department of Food Hygiene, Safety and Technology, Faculty of Veterinary Medicine, Zagazig University, Zagazig City, Egypt
| | - Asmaa B. M. B. Tahoun
- Department of Food Hygiene, Safety and Technology, Faculty of Veterinary Medicine, Zagazig University, Zagazig City, Egypt
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17
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Mohammed AR, El-Said EI, Abd ElAal SF, Kamal RM. Screening of antibiogram, virulence factors, and biofilm production of Staphylococcus aureus and the bio-control role of some probiotics as alternative antibiotics. Open Vet J 2024; 14:176-185. [PMID: 38633196 PMCID: PMC11018438 DOI: 10.5455/ovj.2024.v14.i1.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Accepted: 12/15/2023] [Indexed: 04/19/2024] Open
Abstract
Background Food safety is a serious challenge in the face of increasing population and diminishing resources. Staphylococcus aureus is a critical foodborne pathogen characterized by its capability to secret a diverse range of heat-resistant enterotoxins. Antibiotic usage in dairy herds resulted in the occurrence of antimicrobial resistance (AMR) patterns among bacterial species, which were consequently transmitted to humans via dairy products. Lactic acid bacteria (LAB) produce bacteriocins, which provide an excellent source of natural antimicrobials with the further advantage of being environmentally friendly and safe. Aim Detection of multidrug resistance (MDR) S. aureus isolates in concerned samples, molecular characteristics, biofilm production, and the inhibitory role of LAB against it. Methods Random samples of raw milk and other dairy products were analyzed for S. aureus isolation. Phenotypic and genotypic assessment of AMR was performed, in addition to detection of classical enterotoxin genes of S. aureus. Finally, evaluation of the antimicrobial action of some Lactobacillus strains against S. aureus. Results Incidence rates of presumptive S. aureus in raw milk, Kariesh cheese, and yogurt samples were 50%, 40%, and 60%, respectively. The highest resistance of S. aureus was to Kanamycin (100%) and Nalidixic acid (89.3%), respectively. (78.66%) of S. aureus were MDR. 11.1% of S. aureus carried mecA gene. In concern with enterotoxins genes, PCR showed that examined isolates harbored sea with a percentage of (22.2%), while sed was found in (11.1%) of isolates. Regarding biofilm production, (88.88%) of S. aureus were biofilm producers. Finally, agar well diffusion showed that Lactobacillus acidophilus had the strongest antimicrobial action against S. aureus with inhibition zone diameter ranging from 18 to 22 mm. Conclusion There is a widespread prevalence of MDR S. aureus in raw milk and dairy products. Production of staphylococcal enterotoxins, as well as biofilm production are responsible for public health risks. Therefore, installing proper hygienic routines and harsh food safety policies at food chain levels is substantial.
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Affiliation(s)
- Aya R. Mohammed
- Department of Food Control, Zagazig University, Zagazig, Egypt
| | | | | | - Rania M. Kamal
- Department of Food Control, Zagazig University, Zagazig, Egypt
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Capri FC, Di Leto Y, Presentato A, Mancuso I, Scatassa ML, Alduina R. Characterization of Staphylococcus Species Isolates from Sheep Milk with Subclinical Mastitis: Antibiotic Resistance, Enterotoxins, and Biofilm Production. Foodborne Pathog Dis 2024; 21:10-18. [PMID: 37922428 DOI: 10.1089/fpd.2023.0003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2023] Open
Abstract
Subclinical mastitis represents one of the most contagious diseases affecting animals involved in dairy production systems. Although coagulase-negative staphylococci (CoNSs) have been considered minor pathogens for many years, they have recently emerged as opportunistic pathogens in mastitis disorders. The objectives of this work were to assess the antimicrobial resistance profile and the ability to produce a biofilm in comparison with a reference strain and to search for genes related to biofilm production, antimicrobial resistance, and enterotoxins in 18 isolates of Staphylococcus species from the milk of sheep with subclinical mastitis, collected from different Sicilian farms. This knowledge is essential to provide basic information on the pathogenicity and virulence of staphylococcal species and their impact on animal health. All isolates were resistant to ampicillin, 88.8% to streptomycin, 77.7% to gentamicin, 44.4% to chloramphenicol, 27.7% to erythromycin, and 11.1% to tetracycline, and two isolates were strong biofilm producers. Antibiotic resistance gene profiling showed that 16.6% of isolates possess the blaZ gene, whereas the search of biofilm-associated genes revealed the occurrence of the sasC gene in 33.3% of isolates, the ica gene in 27.7%, and bap and agr (accessory gene regulator) genes in 16.6% of isolates. Altogether, the results of this study indicate that CoNSs can acquire virulence genes and could have a role as pathogens in subclinical mastitis.
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Affiliation(s)
- Fanny Claire Capri
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo, Italy
| | - Ylenia Di Leto
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo, Italy
| | - Alessandro Presentato
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo, Italy
| | - Isabella Mancuso
- Istituto Zooprofilattico Sperimentale della Sicilia "Adelmo Mirri," Palermo, Italy
| | - Maria Luisa Scatassa
- Istituto Zooprofilattico Sperimentale della Sicilia "Adelmo Mirri," Palermo, Italy
| | - Rosa Alduina
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo, Italy
- National Biodiversity Future Center, Palermo, Italy
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Rahman S, Saha S, Dasgupta SB, Das AK. Putative staphylococcal enterotoxin possesses two common structural motifs for MHC-II binding. Int J Biol Macromol 2024; 256:128437. [PMID: 38013079 DOI: 10.1016/j.ijbiomac.2023.128437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 11/20/2023] [Accepted: 11/23/2023] [Indexed: 11/29/2023]
Abstract
Staphylococcus aureus has become a significant cause of health risks in humankind. Staphylococcal superantigens (SAgs) or enterotoxins are the key virulent factors that can exhibit acute diseases to severe life-threatening conditions. Recent literature reports S. aureus has steadily gained new enterotoxin genes over the past few decades. In spite of current knowledge of the established SAgs, several questions on putative enterotoxins are still remaining unanswered. Keeping that in mind, this study sheds light on a putative enterotoxin SEl26 to characterize its structural and functional properties. In-silico analyses indicate its close relation with the conventional SAgs, especially the zinc-binding SAgs. Additionally, important residues that are vital for the T-cell receptor (TcR) and major histocompatibility complex class II (MHC-II) interaction were predicted and compared with established SAgs. Besides, our biochemical analyses exhibited the binding of this putative enterotoxin with MHC-II, followed by regulating pro-inflammatory and anti-inflammatory cytokines.
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Affiliation(s)
- Shakilur Rahman
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India.
| | - Saradindu Saha
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India
| | - Somdeb Bose Dasgupta
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India
| | - Amit Kumar Das
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India.
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Wiśniewski P, Gajewska J, Zadernowska A, Chajęcka-Wierzchowska W. Identification of the Enterotoxigenic Potential of Staphylococcus spp. from Raw Milk and Raw Milk Cheeses. Toxins (Basel) 2023; 16:17. [PMID: 38251234 PMCID: PMC10819113 DOI: 10.3390/toxins16010017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2023] [Revised: 12/16/2023] [Accepted: 12/27/2023] [Indexed: 01/23/2024] Open
Abstract
This study aimed to genotypic and phenotypic analyses of the enterotoxigenic potential of Staphylococcus spp. isolated from raw milk and raw milk cheeses. The presence of genes encoding staphylococcal enterotoxins (SEs), including the classical enterotoxins (sea-see), non-classical enterotoxins (seg-seu), exfoliative toxins (eta-etd) and toxic shock syndrome toxin-1 (tst-1) were investigated. Isolates positive for classical enterotoxin genes were then tested by SET-RPLA methods for toxin expression. Out of 75 Staphylococcus spp. (19 Staphylococcus aureus and 56 CoNS) isolates from raw milk (49/65.3%) and raw milk cheese samples (26/34.7%), the presence of enterotoxin genes was confirmed in 73 (97.3%) of them. Only one isolate from cheese sample (1.3%) was able to produce enterotoxin (SED). The presence of up to eight different genes encoding enterotoxins was determined simultaneously in the staphylococcal genome. The most common toxin gene combination was sek, eta present in fourteen isolates (18.7%). The tst-1 gene was present in each of the analyzed isolates from cheese samples (26/34.7%). Non-classical enterotoxins were much more frequently identified in the genome of staphylococcal isolates than classical SEs. The current research also showed that genes tagged in S. aureus were also identified in CoNS, and the total number of different genes detected in CoNS was seven times higher than in S. aureus. The obtained results indicate that, in many cases, the presence of a gene in Staphylococcus spp. is not synonymous with the ability of enterotoxins production. The differences in the number of isolates with genes encoding SEs and enterotoxin production may be mainly due to the limit of detection of the toxin production method used. This indicates the need to use high specificity and sensitivity methods for detecting enterotoxin in future studies.
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Affiliation(s)
- Patryk Wiśniewski
- Department of Food Microbiology, Meat Technology and Chemistry, Faculty of Food Science, University of Warmia and Mazury, Plac Cieszyński 1, 10-726 Olsztyn, Poland; (J.G.); (A.Z.); (W.C.-W.)
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21
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Xiao Z, Cheng M, Hu X, Xue M, Jiang N, Liu W, Fan Y, Meng Y, Xu C, Zhou Y. Pathological changes of highly pathogenic Bacillus cereus on Pelodiscus sinensis. Vet Q 2023; 43:1-10. [PMID: 38010068 PMCID: PMC11003482 DOI: 10.1080/01652176.2023.2287191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 11/15/2023] [Indexed: 11/29/2023] Open
Abstract
An outbreak of a disease with a high mortality rate occurred in a Chinese Softshell Turtle (Pelodiscus sinensis) farm in Hubei Province. This study isolated a highly pathogenic Bacillus cereus strain (Y271) from diseased P. sinensis. Y271 has β hemolysis, containing both Hemolysin BL (hblA, hblC, and hblD), Non-hemolytic enterotoxin, NHE (nheA, nheB, and nheC), and Enterotoxin FM (entFM) genes. Y271 is highly pathogenic against P. sinensis with an LD50 = 6.80 × 103 CFU/g weight. B. cereus was detected in multiple tissues of the infected P. sinensis. Among them, spleen tissue showed the highest copy number density (1.54 ± 0.12 × 104 copies/mg). Multiple tissues and organs of diseased P. sinensis exhibited significant pathological damage, especially the spleen, liver, kidney, and intestine. It showed obvious tissue structure destruction, lesions, necrosis, red blood cells, and inflammatory cell infiltration. B. cereus proliferating in the spleen, liver, and other tissues was observed. The intestinal microbiota of the diseased P. sinensis was altered, with a greater abundance of Firmicutes, Fusobacterium, and Actinomyces than in the healthy group. Allobaculum, Rothia, Aeromonas, and Clostridium abundance were higher in the diseased group than in the healthy group. The number of unique microbial taxa (472) in the disease group was lower than that of the healthy group (705). Y271 was sensitive to multiple drugs, including florfenicol, enrofloxacin, neomycin, and doxycycline. B. cereus is the etiological agent responsible for the massive death of P. sinensis and reveals its potential risks during P. sinensis cultivation.
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Affiliation(s)
- Zidong Xiao
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Mengmeng Cheng
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
- College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
| | - Xiaowei Hu
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
- Department of Fisheries Development, College of Fisheries, Henan Normal University, Xinxiang, China
| | - Mingyang Xue
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Nan Jiang
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Wei Liu
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Yuding Fan
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Yan Meng
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Chen Xu
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Yong Zhou
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
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Javed MU, Ijaz M, Durrani AZ, Ali MM. On-farm epidemiology, virulence profiling, and molecular characterization of methicillin-resistant Staphylococcus aureus at goat farms. Microb Pathog 2023; 185:106456. [PMID: 37981077 DOI: 10.1016/j.micpath.2023.106456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 11/13/2023] [Accepted: 11/14/2023] [Indexed: 11/21/2023]
Abstract
Antimicrobial resistance (AMR) becomes a challenging issue that limits the therapeutic options for both veterinary and public health professionals. The current study aimed to investigate the on-farm epidemiology, antibiotics resisting profiling, virulence analysis, and molecular detection of methicillin-resistant Staphylococcus aureus (MRSA) at the caprine-human interface. A total of 768 goat milk samples and 94 skin swabs from farm personnel were collected from 30 goat flocks and processed for isolation of S. aureus. The study isolates were confirmed as MRSA based on the oxacillin and cefoxitin disc diffusion test and the presence of mecA gene. MRSA isolates of goats and human origin were characterized and further evaluated for the presence of virulence genes responsible for intramammary infections and public health hazards. The results revealed 26.82 % and 27.79 % goat milk samples and human samples positive for S. aureus, respectively. A higher MRSA prevalence of 35.92 % and 10.71 % was found in goat and human isolates respectively. The phylogenetic analysis revealed a lesser extent of homology in mecA gene of S. aureus isolates at the caprine-human interface. Moreover, this study revealed strong evolutionary connection between the study isolates and MRSA isolates of Pakistani cattle and buffalo while the in-silico protein analysis showed that all sequences have the same protein motifs resembling penicillin binding protein 2a. The risk factors analysis revealed that teat length, drainage system, hygienic measures during milking, use of teat dip, teat injury, and veterinary services were significantly associated with subclinical mastitis in goats. A total of 43.24 % of local MRSA isolates showed multi-drug resistance (MDR). The isolates showed higher resistance to oxytetracycline followed by gentamicin and vancomycin while moxifloxacin, and linezolid were among the susceptible antibiotics. Local MRSA isolates carried virulence markers (nuc and coag genes) and biofilm-associated icaA (43.24 %) and icaD (29.73 %) genes which are responsible for the intramammary infection. The local isolates also carried the virulence genes of public health concern including the enterotoxin C (sec) gene (24.3 %), enterotoxins B (seb) gene (5.41 %), and enterotoxin D (sed) gene (2.7 %). Enterotoxins A (sea) and E (see) genes were not detected in any isolate. The study concluded that MRSA is an emerging and prevailing pathogen in dairy goats with a high potential to transmit to associated human beings. The presence of a variety of virulence factors as well as the associated antibiotic resistance makes MRSA a potential threat at animal-human interface and thus demands further research.
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Affiliation(s)
- Muhammad Umar Javed
- Department of Veterinary Medicine, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Muhammad Ijaz
- Department of Veterinary Medicine, University of Veterinary and Animal Sciences, Lahore, Pakistan.
| | - Aneela Zameer Durrani
- Department of Veterinary Medicine, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Muhammad Muddassir Ali
- Institute of Biochemistry and Biotechnology, University of Veterinary and Animal Sciences, Lahore, Pakistan
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23
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Hsieh HC, Chen CC, Chou PH, Liu WC, Wu SC. Induction of neutralizing antibodies and mucosal IgA through intranasal immunization with the receptor binding domain of SARS-CoV-2 spike protein fused with the type IIb E. coli heat-labile enterotoxin A subunit. Antiviral Res 2023; 220:105752. [PMID: 37949318 DOI: 10.1016/j.antiviral.2023.105752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 11/03/2023] [Accepted: 11/03/2023] [Indexed: 11/12/2023]
Abstract
The outbreak of SARS-CoV-2 infections had led to the COVID-19 pandemic which has a significant impact on global public health and the economy. The spike (S) protein of SARS-CoV-2 contains the receptor binding domain (RBD) which binds to human angiotensin-converting enzyme 2 receptor. Numerous RBD-based vaccines have been developed and recently focused on the induction of neutralizing antibodies against the immune evasive Omicron BQ.1.1 and XBB.1.5 subvariants. In this preclinical study, we reported the use of a direct fusion of the type IIb Escherichia coli heat-labile enterotoxin A subunit with SARS CoV-2 RBD protein (RBD-LTA) as an intranasal vaccine candidate. The results showed that intranasal immunization with the RBD-LTA fusion protein in BALB/c mice elicited potent neutralizing antibodies against the Wuhan-Hu-1 and several SARS-CoV-2 variants as well as the production of IgA antibodies in bronchoalveolar lavage fluids (BALFs). Furthermore, the heterologous RBD representing the same strains used in the bivalent mRNA vaccine were used as a second-dose RBD-LTA/RBD protein booster after bivalent mRNA vaccination. The results showed that the neutralizing antibody titers elicited by the intranasal bivalent RBD-LTA/RBD protein booster were similar to the intramuscular bivalent mRNA booster, but the RBD-specific IgA titers in sera and BALFs significantly increased. Overall, this preclinical study suggests that the RBD-LTA fusion protein could be a promising candidate as a mucosal booster COVID-19 vaccine.
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Affiliation(s)
- He-Chin Hsieh
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, 30013, Taiwan.
| | - Chung-Chu Chen
- Department of Internal Medicine, MacKay Memorial Hospital, Hsinchu, 30071, Taiwan; Teaching Center of Natural Science, Minghsin University of Science and Technology, Hsinchu, 30401, Taiwan.
| | - Pin-Han Chou
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, 30013, Taiwan.
| | - Wen-Chun Liu
- Biomedical Translation Research Center, Academia Sinica, Taipei, 11529, Taiwan.
| | - Suh-Chin Wu
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, 30013, Taiwan; Department of Medical Science, National Tsing Hua University, Hsinchu, 30013, Taiwan; Adimmune Corporation, Taichung, 42723, Taiwan.
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Cai H, Li X, Zhang C, Zhong H, Xie Y, Huang L, Zhang B, Long Y, Zhou Z, Liang B. Molecular characterisation of Staphylococcus aureus in school-age children in Guangzhou: associations among agr types, virulence genes, sequence types, and antibiotic resistant phenotypes. BMC Microbiol 2023; 23:368. [PMID: 38017399 PMCID: PMC10685675 DOI: 10.1186/s12866-023-03126-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 11/17/2023] [Indexed: 11/30/2023] Open
Abstract
BACKGROUND Staphylococcus aureus, one of the most prevalent opportunistic pathogens, mainly colonizes the nasal cavity and is a risk factor for severe infections. Virulence factors and accessory gene regulator (agr) are key to the severity and diversity of staphylococcal infection. In this study, we aimed to characterise S. aureus agr-types and virulence genes and correlated them with genetic background and antibiotic-resistant phenotypes. RESULTS Agr types were identified in 704 isolates (98.5%), with only 11 isolates were negative for agr type. Most of our isolates were classified as agr type I, followed by types III, II and IV. The enterotoxin c gene (sec) was detected in 48.6% of isolates, showing the highest prevalence among the five enterotoxin genes detected. The positivity rates for the lukS/F-PV and tsst genes were 4% and 2.2%, respectively, while neither sed nor SasX were detected. ST45, ST59, ST338, ST188, ST6, ST7, ST22, ST25, ST398, and ST944 belonged to agr I group, while ST5 and ST15 belonged to agr II group. ST30 and ST1 were classified into agr III group, and ST121 was assigned into agr IV group. The tsst gene was found exclusively within agr I and III types belonging to ST7 and ST30 isolates, while the lukS/F-PV was predominantly carried by agr I type isolates primarily within CC59 and CC22 clones. Among the methicillin-resistant S. aureus (MRSA) isolates, 89.7% belonged to agr I group, and 97.8% of rifampicin-resistant or intermediate isolates were assigned to agr I group. MRSA isolates harboured more tested virulence genes compared to methicillin-susceptible S. aureus isolates. CONCLUSIONS We characterized the distributions of agr types and eight major virulence genes of 715 S. aureus isolates, and our findings revealed clear associations between agr types and STs, as well as virulence genes, and drug resistant phenotypes.
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Affiliation(s)
- Hao Cai
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, People's Republic of China
| | - Xueying Li
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, People's Republic of China
| | - Chao Zhang
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, People's Republic of China
- Clinical Laboratory, Longgang District Maternity and Child Healthcare Hospital, Shenzhen, People's Republic of China
| | - Huamin Zhong
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, People's Republic of China
| | - Yongqiang Xie
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, People's Republic of China
| | - Lianfen Huang
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, People's Republic of China
| | - Baidu Zhang
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, People's Republic of China
| | - Yan Long
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, People's Republic of China
| | - Zhenwen Zhou
- National Clinical Laboratory on Tuberculosis, Beijing Key Laboratory for Drug-Resistant Tuberculosis Research, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Institute, Beijing, People's Republic of China.
| | - Bingshao Liang
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, People's Republic of China.
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陈 建, 王 旭, 李 文, 陈 敏, 周 俊, 姚 振, 傅 锦, 叶 小. [Screening of pathogenic molecular markers of Staphylococcus aureus in children based on whole genome sequencing technology]. Zhongguo Dang Dai Er Ke Za Zhi 2023; 25:1161-1169. [PMID: 37990462 PMCID: PMC10672960 DOI: 10.7499/j.issn.1008-8830.2304128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 10/08/2023] [Indexed: 11/23/2023]
Abstract
OBJECTIVES To explore the molecular characteristics of Staphylococcus aureus (S. aureus) in children, and to compare the molecular characteristics of different types of strains (infection and colonization strains) so as to reveal pathogenic molecular markers of S. aureus. METHODS A cross-sectional study design was used to conduct nasopharyngeal swab sampling from healthy children in the community and clinical samples from infected children in the hospital. Whole genome sequencing was used to detect antibiotic resistance genes and virulence genes. A random forest method to used to screen pathogenic markers. RESULTS A total of 512 S. aureus strains were detected, including 272 infection strains and 240 colonization strains. For virulence genes, the carrying rates of enterotoxin genes (seb and sep), extracellular enzyme coding genes (splA, splB, splE and edinC), leukocytotoxin genes (lukD, lukE, lukF-PV and lukS-PV) and epidermal exfoliating genes (eta and etb) in infection strains were higher than those in colonization strains. But the carrying rates of enterotoxin genes (sec, sec3, seg, seh, sei, sel, sem, sen, seo and seu) were lower in infection strains than in colonization strains (P<0.05). For antibiotic resistance genes, the carrying rates of lnuA, lnuG, aadD, tetK and dfrG were significantly higher in infection strains than in colonization strains (P<0.05). The accuracy of cross-validation of the random forest model for screening pathogenic markers of S. aureus before and after screening was 69% and 68%, respectively, and the area under the curve was 0.75 and 0.70, respectively. The random forest model finally screened out 16 pathogenic markers (sem, etb, splE, sep, ser, mecA, lnuA, sea, blaZ, cat(pC233), blaTEm-1A, aph(3')-III, ermB, ermA, ant(9)-Ia and ant(6)-Ia). The top five variables in the variable importance ranking were sem (OR=0.40), etb (OR=3.95), splE (OR=1.68), sep (OR=3.97), and ser (OR=1.68). CONCLUSIONS The random forest model can screen out pathogenic markers of S. aureus and exhibits a superior predictive performance, providing genetic evidence for tracing highly pathogenic S. aureus and conducting precise targeted interventions.
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Yang J, Li Y, Meng L. Combination of Bifidobacterium breve and antibiotics against Clostridioides difficile: effect of the time interval of combination on antagonistic activity. Int Microbiol 2023; 26:833-840. [PMID: 36808573 DOI: 10.1007/s10123-023-00340-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 02/06/2023] [Accepted: 02/13/2023] [Indexed: 02/21/2023]
Abstract
Co-administration of probiotics and antibiotics has been used to prevent or treat primary Clostridioides difficile (pCDI), and the closer the interval between the combination, the more effective it is, but the reason behind this is unknown. In this study, the cell-free culture supernatant (CFCS) of Bifidobacterium breve YH68 was used in combination with vancomycin (VAN) and metronidazole (MTR) to treat C. difficile cells. The growth and biofilm production of C. difficile under different co-administration time interval treatments were determined by optical density and crystalline violet staining, respectively. The toxin production of C. difficile was determined by enzyme immunoassay, and the relative expressions of C. difficile virulence genes tcdA and tcdB were determined by real-time qPCR method. Meanwhile, the types and contents of organic acids in YH68-CFCS were investigated by LC-MS/MS. The results showed that YH68-CFCS in combination with VAN or MTR significantly inhibited the growth, biofilm production, and toxin production of C. difficile in the effective time interval range (0-12 h) but did not affect the expression level of C. difficile virulence genes. In addition, the effective antibacterial component of YH68-CFCS is lactic acid (LA).
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Affiliation(s)
- Jingpeng Yang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, China.
| | - Yanan Li
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, China
| | - Lingtong Meng
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, China.
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Jovanovic J, Rajkovic A. Bacillus cereus Sensu Lato Accelerate Cellular Bioenergetic Metabolism of Human Colorectal Adenocarcinoma Caco-2 Cell Line. Foodborne Pathog Dis 2023; 20:514-520. [PMID: 37831922 DOI: 10.1089/fpd.2023.0030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2023] Open
Abstract
How foodborne enterotoxigenic Bacillus cereus rewires energy metabolism during intestinal tract infection is still not understood. In this study, we used the Seahorse XFe technology to simultaneously analyze oxygen consumption and acidification rates to estimate bioenergetic changes in the intestinal Caco-2 cell line after exposure to the B. cereus sensu lato (s.l.) enterotoxin-producing pathotypes, American Type Culture Collection (ATCC) 14579 (836), NVH0391-98 (828), and NVH0075/95 (825). Infection of Caco-2 led to a more energetic phenotype due to increased flux through oxidative phosphorylation and glycolysis. Strain 836 caused the most pronounced effects toward the specific energy phenotype, followed by strains 828 and 825. However, the metabolic potential of Caco-2 cells was most strongly induced by the 828 strain. Furthermore, infected cells manifested an increased adenosine triphosphate (ATP) production rate. Strain 828 caused the highest glycolytic and mitochondrial ATP production rates, followed by the 836 and 825 B. cereus s.l. strains. The glycolytic stress assay showed that strains 828 and 826 slightly increased compensatory glycolysis, providing a better understanding of the pathogenicity of this versatile pathogen. The results of this study underline that extracellular flux measurement can be used to accurately estimate bioenergetic perturbations of Caco-2 cells as a consequence of infection. Our findings enhance our understanding of how intestinal cells adjust their metabolism during infection with B. cereus s.l.
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Affiliation(s)
- Jelena Jovanovic
- Department of Food Technology, Safety and Health, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Andreja Rajkovic
- Department of Food Technology, Safety and Health, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
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Chen Q, Zhao G, Yang W, Chen F, Qi Y, Lou Z. Investigation into the prevalence of enterotoxin genes and genetic background of Staphylococcus aureus isolates from retain foods in Hangzhou, China. BMC Microbiol 2023; 23:294. [PMID: 37848808 PMCID: PMC10580612 DOI: 10.1186/s12866-023-03027-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 09/20/2023] [Indexed: 10/19/2023] Open
Abstract
BACKGROUND Staphylococcus aureus expresses numerous toxins, many of which are strongly believed to be responsible for specific symptoms and even diseases, making it significant in the pathogenesis of human health. Enterotoxins, which are vital toxins, are associated with foodborne illnesses that manifest through symptoms like vomiting and diarrhea. In the present study, 264 S. aureus isolates obtained from various retail foods in Hangzhou, China were further investigated the profiles of enterotoxin genes and genetic backgrounds. RESULTS Approximately, 64.02% of the isolates from diverse sources contained at least one Staphylococcal Enterotoxin (SE) genes, displaying a total of 36 distinct combinations. Enterotoxin gene cluster (egc) encoded enterotoxin genes, normally designated by seg, sei, sem, sen, seo and selu, plus with sep were more frequently detected (33.73%, each). In contrast, see, ses and set were absent in any of the isolates tested. A total of 44 sequence types (STs), 20 clonal complexes (CCs) and 66 different staphylococcal protein A (spa) types (including six novel types) were identified among those 169 SE-positive isolates. Moreover, nineteen methicillin-resistant Staphylococcus aureus (MRSA) isolates were identified. The majority of those isolates belonged to the CC59-Sccmec IVa cluster and carried the seb-sek-seq gene cluster. The egc cluster, either coexisting with or without other enterotoxin genes, was observed in all isolates allocated into CC5, CC9, CC20, CC25, CC72 and ST672. Irrespective of the spa types and origins of the food, it appeared that seh was a distinct genetic element present in isolates belonging to the CC1 clonal lineage. CONCLUSIONS The results not only proposed a suspected relationship between distribution of enterotoxigenic strains and genetic backgrounds, but also attributed the presence of novel enterotoxins to potential hazards in food safety.
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Affiliation(s)
- Qi Chen
- Hangzhou Traditional Chinese Medicine Hospital Affiliated to Zhejiang Chinese Medical University, 310000, Hangzhou, China.
| | - Gang Zhao
- Hangzhou Center for Disease Control and Prevention, 310021, Hangzhou, China
| | - Wei Yang
- Hangzhou Traditional Chinese Medicine Hospital Affiliated to Zhejiang Chinese Medical University, 310000, Hangzhou, China
| | - Fuhong Chen
- Hangzhou Traditional Chinese Medicine Hospital Affiliated to Zhejiang Chinese Medical University, 310000, Hangzhou, China
| | - Yan Qi
- Hangzhou Traditional Chinese Medicine Hospital Affiliated to Zhejiang Chinese Medical University, 310000, Hangzhou, China
| | - Zhengqing Lou
- Hangzhou Traditional Chinese Medicine Hospital Affiliated to Zhejiang Chinese Medical University, 310000, Hangzhou, China.
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Kamala K, Sivaperumal P. Prevalence of enterotoxin genes of Staphylococcus sp. isolated from marine fish to reveal seafood contamination. Mar Pollut Bull 2023; 195:115464. [PMID: 37666137 DOI: 10.1016/j.marpolbul.2023.115464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 08/22/2023] [Accepted: 08/26/2023] [Indexed: 09/06/2023]
Abstract
Seafood is a valuable nutritional source, but it is highly susceptible to bacterial contamination, posing a severe health risk to humans. Enterotoxin-producing genes carrying Staphylococcus sp. are a significant concern in marine fish. This study aimed to investigate the prevalence of enterotoxin genes in Staphylococcus sp. isolated from 17 common fish species and emphasise the need for improving seafood quality and hygiene. The potential risks of contamination by enterotoxin-producing Staphylococcus sp. were assessed. The results indicated the risk associated with the consumption of contaminated seafood, especially from marketed and frozen samples. Gene expression analysis on a heat map revealed that samples stored in markets are heavily loaded with Staphylococcus enterotoxin genes due to the unhygienic water that was used from the local markets for fish processing. To enhance seafood quality, effective measures on handling and storage should be regularly monitored, and they must be implemented throughout the local seafood markets.
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Affiliation(s)
- Kannan Kamala
- Centre for Marine Actinobacterial Research (CMAR), Department of Physiology, Saveetha Dental College and Hospitals, Saveetha Institute of Medical & Technical Sciences, Saveetha University, Chennai 600077, Tamil Nadu, India
| | - Pitchiah Sivaperumal
- Marine Biomedical Research Lab & Environmental Toxicology Unit, Centre for Marine Research and Conservation, Saveetha Dental College and Hospitals, Saveetha Institute of Medical & Technical Sciences, Saveetha University, Chennai 600077, Tamil Nadu, India.
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Zhao G, Lou Z, Zhu Z, Lai X, Li J, Lou X, Huang L, Chen Q. Epidemiological and molecular evidence of foodborne poisoning outbreak caused by enterotoxin gene cluster-harboring Staphylococcus aureus of new sequence type 7591. Int J Infect Dis 2023; 135:132-135. [PMID: 37619662 DOI: 10.1016/j.ijid.2023.08.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 08/06/2023] [Accepted: 08/07/2023] [Indexed: 08/26/2023] Open
Abstract
OBJECTIVES This paper presented a detailed analysis of the epidemiology and molecular characteristics of staphylococcal food poisoning (SFP) that occurred in a hotel in Hangzhou. METHODS A total of 46 guests at the hotel underwent an epidemiological survey. Samples of stool from patients, vomit, swabs from the kitchen, leftover food items, and anal swabs from food handlers were taken and investigated for the presence of potential pathogenic bacteria. Molecular techniques and whole genome sequencing were performed to track the evolution of Staphylococcus aureus associated with the outbreak of SFP. RESULTS Forty-six individuals displayed gastrointestinal symptoms. Seventeen isolates of S. aureus were discovered to carry the seg, sei, sem, sen, seo, and selu genes found in a specific enterotoxin gene cluster (egc) operon, but without the presence of classical enterotoxins such as SEA ∼ SEE. All egc-positive isolates shared identical pulsed-field gel electrophoresis profiles and were classified under new ST7591 (Clonal Complex 72) with identical spa typing t148. In addition, some isolates of S. aureus obtained from food sources sold in Hangzhou over the past 3 years and carrying egc genes were grouped under the ST72 lineage (CC72). Through whole genome sequencing, a strong genetic connection was revealed between these egc-positive isolates and clinical ST72 S. aureus found in China. CONCLUSIONS S. aureus with non-classical egc enterotoxins was suggested to be a potential cause of SFP in humans.
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Affiliation(s)
- Gang Zhao
- Hangzhou Center for Disease Control and Prevention, Hangzhou, China
| | - Zhengqing Lou
- Hangzhou Traditional Chinese Medicine Hospital Affiliated to Zhejiang Chinese Medical University, Hangzhou, China
| | - Zhiyong Zhu
- Tonglu Center for Disease Control and Prevention, Hangzhou, China
| | - Xuying Lai
- Tonglu Center for Disease Control and Prevention, Hangzhou, China
| | - Jun Li
- Hangzhou Center for Disease Control and Prevention, Hangzhou, China
| | - Xiuqin Lou
- Hangzhou Center for Disease Control and Prevention, Hangzhou, China
| | - Liming Huang
- Hangzhou Center for Disease Control and Prevention, Hangzhou, China
| | - Qi Chen
- Hangzhou Center for Disease Control and Prevention, Hangzhou, China; Hangzhou Traditional Chinese Medicine Hospital Affiliated to Zhejiang Chinese Medical University, Hangzhou, China.
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Banaszkiewicz S, Tabiś A, Wałecki B, Łyżwińska K, Bystroń J, Bania J. spa Types and Staphylococcal Enterotoxin Production of Staphylococcus aureus Isolated from Wild Boar. Microb Ecol 2023; 86:2184-2191. [PMID: 37156959 PMCID: PMC10497643 DOI: 10.1007/s00248-023-02236-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 05/01/2023] [Indexed: 05/10/2023]
Abstract
Little is known about the structure of S. aureus population and the enterotoxin gene content in wild boar. In 1025 nasal swabs from wild boars, 121 S. aureus isolates were identified. Staphylococcal enterotoxin (SE) genes were identified in 18 isolates (14.9%). The seb gene was found in 2 S. aureus isolates, sec in 2 isolates, the see and seh genes were found in 4 and 11 isolates, respectively. The production of SEs was evaluated in bacteria grown in microbial broth. Concentration of SEB reached 2.70 µg/ml after 24 h and 4.46 µg/ml at 48 h. SEC was produced at 952.6 ng/ml after 24 h and 7.2 µg/ml at 48 h. SEE reached 124.1 ng/ml after 24 h and 191.6 ng/ml at 48 h of culture. SEH production reached 4.36 µg/ml at 24 h and 5.42 µg/ml at 48 h of culture. Thirty-nine spa types were identified among S. aureus isolates. The most prevalent spa types were t091 and t1181, followed by t4735 and t742, t3380 and t127. Twelve new spa types, i.e., t20572‒t20583 were identified. The wild boar S. aureus population was shown to contain previously identified animal/human-associated spa types and spa types not identified in humans or animals. We also indicate that wildlife animals can be a significant reservoir of see-positive S. aureus.
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Affiliation(s)
- Sylwia Banaszkiewicz
- Department of Food Hygiene and Consumer Health Protection, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
| | - Aleksandra Tabiś
- Department of Food Hygiene and Consumer Health Protection, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
| | - Bartosz Wałecki
- Department of Food Hygiene and Consumer Health Protection, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
| | - Karolina Łyżwińska
- Department of Food Hygiene and Consumer Health Protection, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
| | - Jarosław Bystroń
- Department of Food Hygiene and Consumer Health Protection, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
| | - Jacek Bania
- Department of Food Hygiene and Consumer Health Protection, Wrocław University of Environmental and Life Sciences, Wrocław, Poland.
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Kordus SL, Kroh HK, Rodríguez RC, Shrem RA, Peritore-Galve FC, Shupe JA, Wadzinski BE, Lacy DB, Spiller BW. Nanobodies against C. difficile TcdA and TcdB reveal unexpected neutralizing epitopes and provide a toolkit for toxin quantitation in vivo. PLoS Pathog 2023; 19:e1011496. [PMID: 37871122 PMCID: PMC10621975 DOI: 10.1371/journal.ppat.1011496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 11/02/2023] [Accepted: 10/07/2023] [Indexed: 10/25/2023] Open
Abstract
Clostridioides difficile is a leading cause of antibiotic-associated diarrhea and nosocomial infection in the United States. The symptoms of C. difficile infection (CDI) are associated with the production of two homologous protein toxins, TcdA and TcdB. The toxins are considered bona fide targets for clinical diagnosis as well as the development of novel prevention and therapeutic strategies. While there are extensive studies that document these efforts, there are several gaps in knowledge that could benefit from the creation of new research tools. First, we now appreciate that while TcdA sequences are conserved, TcdB sequences can vary across the span of circulating clinical isolates. An understanding of the TcdA and TcdB epitopes that drive broadly neutralizing antibody responses could advance the effort to identify safe and effective toxin-protein chimeras and fragments for vaccine development. Further, an understanding of TcdA and TcdB concentration changes in vivo can guide research into how host and microbiome-focused interventions affect the virulence potential of C. difficile. We have developed a panel of alpaca-derived nanobodies that bind specific structural and functional domains of TcdA and TcdB. We note that many of the potent neutralizers of TcdA bind epitopes within the delivery domain, a finding that could reflect roles of the delivery domain in receptor binding and/or the conserved role of pore-formation in the delivery of the toxin enzyme domains to the cytosol. In contrast, neutralizing epitopes for TcdB were found in multiple domains. The nanobodies were also used for the creation of sandwich ELISA assays that allow for quantitation of TcdA and/or TcdB in vitro and in the cecal and fecal contents of infected mice. We anticipate these reagents and assays will allow researchers to monitor the dynamics of TcdA and TcdB production over time, and the impact of various experimental interventions on toxin production in vivo.
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Affiliation(s)
- Shannon L. Kordus
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Heather K. Kroh
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Rubén Cano Rodríguez
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Rebecca A. Shrem
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - F. Christopher Peritore-Galve
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - John A. Shupe
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Brian E. Wadzinski
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - D. Borden Lacy
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, Tennessee, United States of America
| | - Benjamin W. Spiller
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
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Pineda APA, Cueva CLR, Chacón RD, Ramírez M, de Almeida OGG, de Oliveira DP, Franco BDGM, Lacorte G, Landgraf M, Silva NCC, Pinto UM. Genomic characterization of Staphylococcus aureus from Canastra Minas Artisanal Cheeses. Braz J Microbiol 2023; 54:2103-2116. [PMID: 37594655 PMCID: PMC10485191 DOI: 10.1007/s42770-023-01099-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 08/09/2023] [Indexed: 08/19/2023] Open
Abstract
Canastra Minas Artisanal Cheese is produced in the Brazilian State of Minas Gerais using raw milk, rennet, and pingo, a natural endogenous starter culture (fermented whey) collected from the previous day's production. Due to the use of raw milk, the product can carry microorganisms that may cause foodborne diseases (FBD), including Staphylococcus aureus. Genomic characterization of S. aureus is an important tool to assess diversity, virulence, antimicrobial resistance, and the potential for causing food poisoning due to enterotoxin production. This study is aimed at exploring the genomic features of S. aureus strains isolated from Canastra Minas Artisanal Cheeses. Multilocus sequence typing (MLST) classified these strains as ST1, ST5, and a new profile ST7849 (assigned to the clonal complex CC97). These strains belonged to four spa types: t008, t127, t359, and t992. We identified antimicrobial resistance genes with phenotypic correlation against methicillin (MRSA) and tetracycline. Virulome analysis revealed genes associated with iron uptake, immune evasion, and potential capacity for adherence and biofilm formation. The toxigenic potential included cyto- and exotoxins genes, and all strains presented the genes that encode for Panton-Valentine toxin and hemolysin, and two strains encoded 4 and 8 Staphylococcal enterotoxin (SE) genes. The results revealed the pathogenic potential of the evaluated S. aureus strains circulating in the Canastra region, representing a potential risk to public health. This study also provides useful information to monitor and guide the application of control measures to the artisanal dairy food production chain.
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Affiliation(s)
- Ana P Arellano Pineda
- Food Research Center, Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 580, São Paulo, SP, 05508-000, Brazil
| | - Carmen L Rodríguez Cueva
- Laboratory of Biology and Molecular Genetics, Faculty of Veterinary Medicine, Universidad Nacional Mayor de San Marcos, Lima, 15021, Peru
| | - Ruy D Chacón
- Department of Pathology, School of Veterinary Medicine, University of São Paulo, Av. Prof. Orlando M. Paiva, 87, São Paulo, SP, 05508-270, Brazil
| | - Manuel Ramírez
- Faculty of Science and Health, Peruvian University of Applied Sciences-UPC, Prolongación Primavera 2390, Santiago de Surco, Lima, 15023, Peru
| | - Otávio G G de Almeida
- Department of Clinical Analysis, Toxicology and Food Science, Faculty of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Avenida Do Café, S/N, Ribeirão Preto, SP, 14040-903, Brazil
| | - Débora P de Oliveira
- Food Research Center, Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 580, São Paulo, SP, 05508-000, Brazil
| | - Bernadette D G M Franco
- Food Research Center, Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 580, São Paulo, SP, 05508-000, Brazil
| | - Gustavo Lacorte
- Federal Institute of Minas Gerais - Campus Bambuí, Bambuí, MG, 30575-180, Brazil
| | - Mariza Landgraf
- Food Research Center, Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 580, São Paulo, SP, 05508-000, Brazil
| | - Nathalia Cristina Cirone Silva
- Department of Food Sciences and Nutrition, Faculty of Food Engineering, State University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Uelinton Manoel Pinto
- Food Research Center, Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 580, São Paulo, SP, 05508-000, Brazil.
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Ramadan HA, El-Baz AM, Goda RM, El-Sokkary MMA, El-Morsi RM. Molecular characterization of enterotoxin genes in methicillin-resistant S. aureus isolated from food poisoning outbreaks in Egypt. J Health Popul Nutr 2023; 42:86. [PMID: 37641155 PMCID: PMC10463939 DOI: 10.1186/s41043-023-00416-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Accepted: 07/09/2023] [Indexed: 08/31/2023]
Abstract
BACKGROUND Staphylococcus aureus (S. aureus), especially methicillin-resistant S. aureus (MRSA), is a known disease-causing bacteria with many associated health hazards. Staphylococcal food poisoning can result from staphylococcal enterotoxins (SEs). METHODS In this study, 50 S. aureus isolates were isolated from the gastrointestinal tract (GIT) clinical samples of patients with food poisoning in clinical laboratories at Mansoura University Hospital, Egypt. For determination their antibiogram, these isolates were tested for antimicrobial sensitivity against 12 antimicrobial agents using the agar disk diffusion test. After DNA extraction from the isolates, conventional polymerase chain reaction (PCR) was used to detect mecA and SEs genes. RESULTS As a result, all isolates were ampicillin and cefoxitin-resistant, while 86% (43 of 50) of the tested isolates exhibited multidrug resistance (MDR). In contrast, the highest sensitivity was confirmed against vancomycin, linezolid and quinolones, namely ciprofloxacin and norfloxacin. Although 100% of the isolates were mecA positive, staphylococcal enterotoxin genes set-A, set-B, set-C, set-G, set-M, and set-O genes were detected in 56%, 20%, 8%, 32%, 16%, and 24%, of the tested isolates, respectively. Finally, isolates encompassing SEs genes were used to validate a microarray chip, indicating its potential for a better methodological approach for detecting and identifying SEs in human samples. CONCLUSION The genotypic findings of this study may help explain the enterotoxigenic patterns in S. aureus among Egyptian patients with food poisoning.
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Affiliation(s)
- Heba A Ramadan
- Department of Microbiology and Immunology, Faculty of Pharmacy, Delta University for Science and Technology, Gamasa, 11152, Egypt
| | - Ahmed M El-Baz
- Department of Microbiology and Immunology, Faculty of Pharmacy, Delta University for Science and Technology, Gamasa, 11152, Egypt
| | - Reham M Goda
- Department of Microbiology and Immunology, Faculty of Pharmacy, Delta University for Science and Technology, Gamasa, 11152, Egypt
| | - Mohamed M A El-Sokkary
- Microbiology and Immunology Department, Faculty of Pharmacy, Mansoura University, Mansoura, 35516, Egypt.
| | - Rasha M El-Morsi
- Department of Microbiology and Immunology, Faculty of Pharmacy, Delta University for Science and Technology, Gamasa, 11152, Egypt
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Okuno M, Tsuru N, Yoshino S, Gotoh Y, Yamamoto T, Hayashi T, Ogura Y. Isolation and Genomic Characterization of a Heat-Labile Enterotoxin 1-Producing Escherichia fergusonii Strain from a Human. Microbiol Spectr 2023; 11:e0049123. [PMID: 37432125 PMCID: PMC10434266 DOI: 10.1128/spectrum.00491-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 06/23/2023] [Indexed: 07/12/2023] Open
Abstract
Escherichia fergusonii strains have been isolated from patients with diarrhea, but their virulence determinant has not been well elucidated. Here, we report the first isolation of a heat-labile enterotoxin 1 (LT1)-producing E. fergusonii strain (strain 30038) from a patient in Japan. The complete genome sequence of strain 30038 was determined and subjected to comparative genomics and phylogenetic analyses with 195 publicly available genomes of E. fergusonii. In addition to strain 30038, the elt1 gene was also identified in an E. fergusonii strain that is phylogenetically distinct and which was isolated from poultry in the United Kingdom. Fine genomic comparison revealed that these two strains share comparable elt1-bearing plasmids. However, an intriguing distinction arises in strain 30038, wherein the plasmid has integrated into the chromosome via a recombination process mediated by an insertion sequence. The production of active LT1 toxin by strain 30038 was verified through an in vitro assay using cultured cells. A large plasmid carrying 11 antimicrobial resistance genes was also identified in strain 30038. Our results indicate that extensive surveillance of elt1-positive E. fergusonii strains as diarrheagenic pathogens is needed. IMPORTANCE Escherichia fergusonii, a species closely related to Escherichia coli, is known to cause sporadic conditions in humans, including diarrhea. However, the critical virulence factors in E. fergusonii clinical isolates remain to be identified. This study shows the first isolation of an E. fergusonii strain carrying the elt1 gene, which encodes heat-labile enterotoxin 1, from a patient with diarrhea. Our analysis of public databases also revealed the presence of elt1-positive E. fergusonii strains isolated from poultry in the United Kingdom. Interestingly, while the elt1 gene in the poultry isolate was present on a large plasmid, in the human isolate it was integrated into the chromosome, which may confer stability on the elt1-carrying genetic element. Our findings highlight the need for extensive surveillance of elt1-positive E. fergusonii strains in livestock animals.
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Affiliation(s)
- Miki Okuno
- Division of Microbiology, Department of Infectious Medicine, Kurume University School of Medicine, Kurume, Japan
| | - Nami Tsuru
- Miyazaki Prefectural Institute for Public Health and Environment, Miyazaki, Japan
| | - Shuji Yoshino
- Miyazaki Prefectural Institute for Public Health and Environment, Miyazaki, Japan
| | - Yasuhiro Gotoh
- Department of Bacteriology, Faculty of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Takeshi Yamamoto
- Division of Microbiology, Department of Infectious Medicine, Kurume University School of Medicine, Kurume, Japan
| | - Tetsuya Hayashi
- Department of Bacteriology, Faculty of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Yoshitoshi Ogura
- Division of Microbiology, Department of Infectious Medicine, Kurume University School of Medicine, Kurume, Japan
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Tasanapak K, Kucharoenphaibul S, Wongwigkarn J, Sitthisak S, Thummeepak R, Chaibenjawong P, Chatdumrong W, Nimanussornkul K. Prevalence and virulence genes of Staphylococcus aureus from food contact surfaces in Thai restaurants. PeerJ 2023; 11:e15824. [PMID: 37601259 PMCID: PMC10434075 DOI: 10.7717/peerj.15824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 07/10/2023] [Indexed: 08/22/2023] Open
Abstract
Background Staphylococcus aureus is one of the most common pathogens responsible for food poisoning due to its ability to produce staphylococcal enterotoxin (SE). S. aureus can form biofilms on the surfaces of food processing devices, enabling the distribution of SE on foods through cross-contamination events. Thailand is known for its exotic cuisine, but there is no data on the prevalence of SE-harboring S. aureus in restaurants in Thailand. Methods In this study, we conducted surface swabs on surfaces of kitchen utensil that come into contact with food and on the hands of food handlers working in restaurants in the north part of Thailand. Isolated S. aureus was investigated for biofilm formation, virulence, and SE genes. Results Two hundred S. aureus were isolated from 650 samples. The highest prevalence of S. aureus contamination was detected on the hands of food handlers (78%), followed by chopping boards (26%), plates (23%), knives (16%), spoons (13%), and glasses (5%). All of them were methicillin-sensitive S. aureus (MSSA) and the mecA gene was not present in any strains. Biofilm formation was detected using the CRA method, and 49 (24.5%) were identified as biofilm-producing strains, with the hands of food handlers identified as the primary source of biofilm-producing strains. The prevelence of biofilm-related adhesion genes detected were: icaAD (13%), fnbA (14.5%), cna (6.5%), and bap (0.5%). Two classical enterotoxin genes, sec and sed, were also found in four and six of the S. aureus isolates, respectively, from hands and utensils. Conclusion The highest prevelence of S. aureus was detected on the hands of food handlers. S. aureus strains with biofilm and enterotoxin production abilities were discovered on food contact surfaces and the hands of food handlers, implying significant risk of food contamination from these sources that could be harmful to consumers. To avoid cross-contamination of food with food contact items, the food handlers' hands should be properly washed, and all food preparation equipment should be thoroughly cleaned.
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Affiliation(s)
- Kannipa Tasanapak
- Microbiology and Parasitology, Naresuan University, Muang, Phitsanulok, Thailand
- Centre of Excellence in Medical Biotechnology, Faculty of Medical Science, Naresuan University, Muang, Phitsanulok, Thailand
| | | | - Jintana Wongwigkarn
- Microbiology and Parasitology, Naresuan University, Muang, Phitsanulok, Thailand
| | - Sutthirat Sitthisak
- Microbiology and Parasitology, Naresuan University, Muang, Phitsanulok, Thailand
| | - Rapee Thummeepak
- Microbiology and Parasitology, Naresuan University, Muang, Phitsanulok, Thailand
| | | | - Wassana Chatdumrong
- Microbiology and Parasitology, Naresuan University, Muang, Phitsanulok, Thailand
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Khoothiam K, Prapasawat W, Yosboonruang A, Rawangkan A, Phuangsri C, Rupprom K, Kraivuttinun P, Tanomsridachchai W, Suthienkul O, Siriphap A. Prevalence, antimicrobial resistance, and enterotoxin gene profiles of Staphylococcus aureus isolated from mobile phones of the food vendors in Phayao province, Thailand. Ann Clin Microbiol Antimicrob 2023; 22:68. [PMID: 37550710 PMCID: PMC10408101 DOI: 10.1186/s12941-023-00621-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 07/23/2023] [Indexed: 08/09/2023] Open
Abstract
BACKGROUND Mobile phones are widely used and may cause bacterial pathogens to spread among various professionals. Staphylococcus aureus from the mobile phones can contaminate the hands of food vendors and food during the cooking or packaging process. This research aimed to determine the prevalence, enterotoxin genes, and antimicrobial resistance (AMR) profiles of S. aureus contaminating the vendors' mobile phones. METHODS In this study, 266 mobile phone samples were randomly collected from food vendors selling food on walking streets (n = 139) and in food centers (n = 127) in Phayao province. All samples were identified as S. aureus by the conventional culture method and confirmed species-specific gene by polymerase chain reaction (PCR). Then, all identified S. aureus isolates were tested for antimicrobial susceptibility by broth microdilution method and for the presence of staphylococcal enterotoxin (SE) genes by PCR. RESULTS The results showed that 12.8% of the mobile phones collected were contaminated with S. aureus. Of 49 S. aureus isolates obtained, 30 (61.2%) were positive for SE genes. The most common SE gene was sea followed by sec, seb, sem, seq, and sel. Moreover, S. aureus was most frequently resistant to penicillin, followed by chloramphenicol and tetracycline, erythromycin, clindamycin, and gentamicin. Methicillin-resistant S. aureus (MRSA), vancomycin-resistant S. aureus (VRSA), and multidrug-resistant (MDR) strains were also detected. CONCLUSIONS This study showed that mobile phones were an intermediate surface for the transmission of S. aureus, including MDR variants. It indicates that hand hygiene and the decontamination of mobile phones are essential to prevent cross-contamination of S. aureus in food settings.
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Affiliation(s)
- Krissana Khoothiam
- Division of Microbiology, School of Medical Sciences, University of Phayao, Phayao, Thailand
| | - Watsawan Prapasawat
- Department of Clinic, Faculty of Veterinary Medicine, Mahanakorn University of Technology, Bangkok, Thailand
| | - Atchariya Yosboonruang
- Division of Microbiology, School of Medical Sciences, University of Phayao, Phayao, Thailand
| | - Anchalee Rawangkan
- Division of Microbiology, School of Medical Sciences, University of Phayao, Phayao, Thailand
| | - Chorpaka Phuangsri
- Division of Microbiology, School of Medical Sciences, University of Phayao, Phayao, Thailand
| | - Kitwadee Rupprom
- Department of Clinical Pathology, Faculty of Medicine Vajira Hospital, Navamindradhiraj University, Bangkok, Thailand
| | - Parinya Kraivuttinun
- Department of Environmental Science, Faculty of Science and Technology, Uttaradit Rajabhat University, Uttaradit, Thailand
| | - Wimonrat Tanomsridachchai
- Department of Clinic, Faculty of Veterinary Medicine, Mahanakorn University of Technology, Bangkok, Thailand
| | - Orasa Suthienkul
- Faculty of Public Health, Mahidol University, Bangkok, 10400, Thailand
| | - Achiraya Siriphap
- Division of Microbiology, School of Medical Sciences, University of Phayao, Phayao, Thailand.
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Etter D, Jenni C, Edwards V, Greutmann M, Waltenspül T, Tasara T, Johler S. Stress Lowers Staphylococcal Enterotoxin C Production Independently of Agr, SarA, and SigB. J Food Prot 2023; 86:100127. [PMID: 37414283 DOI: 10.1016/j.jfp.2023.100127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 06/28/2023] [Accepted: 07/01/2023] [Indexed: 07/08/2023]
Abstract
Staphylococcal enterotoxin C (SEC) can cause staphylococcal food poisoning, one of the most prevalent foodborne intoxications. It is produced by Staphylococcus aureus during growth in the food matrix. While the surrounding bacteria in food matrices usually repress the growth of S.aureus, the organism possesses a remarkable growth advantage under stressful conditions encountered in many foods. Examples for such food matrices are pastry and bakery products with their high sugar content that lowers water availability. While S. aureus can still grow in these challenging environments, it remains unclear how these conditions affect SEC expression. Here, the influence of 30% glucose on sec mRNA in a qPCR assay and SEC protein expression was investigated for the first time in an ELISA. In addition, regulatory knockout mutants Δagr, ΔsarA, and ΔsigB were generated to investigate regulatory gene elements in glucose stress. In five out of seven strains, glucose stress led to a pronounced decrease in sec mRNA transcription and SEC protein levels were substantially lower under glucose stress. It could be shown that key regulatory elements Δagr, ΔsarA, and ΔsigB in strain SAI48 did not contribute to the pronounced downregulation under glucose stress. Based on these findings, glucose effectively lowers SEC synthesis in the food matrix. However, the mechanism by which it acts on toxin expression and regulatory elements in S. aureus remains unclear. Future studies on other regulatory elements and transcriptomics may shed light on the mechanisms.
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Affiliation(s)
- Danai Etter
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 272, 8057 Zurich, Switzerland; Institute for Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, 8092 Zurich, Switzerland
| | - Céline Jenni
- Institute for Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, 8092 Zurich, Switzerland
| | - Veronica Edwards
- Institute for Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, 8092 Zurich, Switzerland
| | - Mariella Greutmann
- Institute for Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, 8092 Zurich, Switzerland
| | - Tabea Waltenspül
- Institute for Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, 8092 Zurich, Switzerland
| | - Taurai Tasara
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 272, 8057 Zurich, Switzerland
| | - Sophia Johler
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 272, 8057 Zurich, Switzerland.
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Cruz-Facundo IM, Adame-Gómez R, Castro-Alarcón N, Toribio-Jiménez J, Castro-Coronel Y, Santiago-Dionisio MC, Leyva-Vázquez MA, Tafolla-Venegas D, Ramírez-Peralta A. Enterotoxigenic profiles and submerged and interface biofilms in Bacillus cereus group isolates from foods. Rev Argent Microbiol 2023; 55:262-271. [PMID: 37019800 DOI: 10.1016/j.ram.2023.01.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 01/24/2023] [Accepted: 01/26/2023] [Indexed: 04/05/2023] Open
Abstract
Biofilm formation by Bacillus cereus strains is now recognized as a systematic contamination mechanism in foods; the aim of this study was to evaluate the production of submerged and interface biofilms in strains of B. cereus group in different materials, the effect of dextrose, motility, the presence of genes related to biofilms and the enterotoxigenic profile of the strains. We determine biofilm production by safranin assay, motility on semi-solid medium, toxin gene profiling and genes related to biofilm production by PCR in B. cereus group isolated from food. In this study, we observe strains used a higher production of biofilms in PVC; in the BHI broth, no submerged biofilms were found compared to phenol red broth and phenol red broth supplemented with dextrose; no strains with the ces gene were found, the enterotoxin profile was the most common the profile that includes genes for the three enterotoxins. We observed a different distribution of tasA and sipW with the origin of isolation of the strain, being more frequent in the strains isolated from eggshell. The production and type of biofilms are differential according to the type of material and culture medium used.
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Affiliation(s)
- Itzel-Maralhi Cruz-Facundo
- Universidad Autónoma de Guerrero, Laboratorio de Investigación en Patometabolismo Microbiano, Facultad de Ciencias Químico Biológicas, Chilpancingo de los Bravo, Guerrero 39070, Mexico
| | - Roberto Adame-Gómez
- Universidad Autónoma de Guerrero, Laboratorio de Investigación en Patometabolismo Microbiano, Facultad de Ciencias Químico Biológicas, Chilpancingo de los Bravo, Guerrero 39070, Mexico
| | - Natividad Castro-Alarcón
- Universidad Autónoma de Guerrero, Laboratorio de Investigación en Microbiología, Facultad de Ciencias Químico Biológicas, Chilpancingo de los Bravo, Guerrero CP39070, Mexico
| | - Jeiry Toribio-Jiménez
- Universidad Autónoma de Guerrero, Laboratorio de Investigación en Microbiología Molecular y Biotecnología Ambiental, Facultad de Ciencias Químico Biológicas, Chilpancingo de los Bravo, Guerrero CP39070, Mexico
| | - Yaneth Castro-Coronel
- Universidad Autónoma de Guerrero, Laboratorio de Investigación en Citopatología e Histoquímica, Facultad de Ciencias Químico Biológicas, Chilpancingo de los Bravo, Guerrero CP39070, Mexico
| | - María-Cristina Santiago-Dionisio
- Universidad Autónoma de Guerrero, Laboratorio de Investigación en Análisis Microbiológicos, Facultad de Ciencias Químico Biológicas, Chilpancingo de los Bravo, Guerrero CP39070, Mexico
| | - Marco-Antonio Leyva-Vázquez
- Universidad Autónoma de Guerrero, Laboratorio de Investigación en Biomedicina Molecular, Facultad de Ciencias Químico Biológicas, Chilpancingo de los Bravo, Guerrero CP39070, Mexico
| | - David Tafolla-Venegas
- Universidad Michoacana de San Nicolás de Hidalgo, Facultad de Biología, Laboratorio de Parasitología, Morelia, Michoacan 58004, Mexico
| | - Arturo Ramírez-Peralta
- Universidad Autónoma de Guerrero, Laboratorio de Investigación en Patometabolismo Microbiano, Facultad de Ciencias Químico Biológicas, Chilpancingo de los Bravo, Guerrero 39070, Mexico.
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Li J, Pradhan A, McClane BA. NanJ Is the Major Sialidase for Clostridium perfringens Type F Food Poisoning Strain 01E809. Infect Immun 2023; 91:e0005323. [PMID: 37212696 PMCID: PMC10269042 DOI: 10.1128/iai.00053-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 05/01/2023] [Indexed: 05/23/2023] Open
Abstract
Clostridium perfringens type F strains cause food poisoning (FP) when they sporulate and produce C. perfringens enterotoxin (CPE) in the intestines. Most type F FP strains carry a chromosomal cpe gene (c-cpe strains). C. perfringens produces up to three different sialidases, named NanH, NanI, and NanJ, but some c-cpe FP strains carry only nanJ and nanH genes. This study surveyed a collection of such strains and showed that they produce sialidase activity when cultured in Todd-Hewitt broth (TH) (vegetative cultures) or modified Duncan-Strong (MDS) medium (sporulating cultures). Sialidase null mutants were constructed in 01E809, a type F c-cpe FP strain carrying the nanJ and nanH genes. Characterization of those mutants identified NanJ as the major sialidase of 01E809 and showed that, in vegetative and sporulating cultures, nanH expression affects nanJ expression and vice versa; those regulatory effects may involve media-dependent changes in transcription of the codY or ccpA genes but not nanR. Additional characterization of these mutants demonstrated the following: (i) NanJ contributions to growth and vegetative cell survival are media dependent, with this sialidase increasing 01E809 growth in MDS but not TH; (ii) NanJ enhances 24-h vegetative cell viability in both TH and MDS cultures; and (iii) NanJ is important for 01E809 sporulation and, together with NanH, CPE production in MDS cultures. Lastly, NanJ was shown to increase CPE-induced cytotoxicity and CH-1 pore formation in Caco-2 cells. Collectively, these results suggest that NanJ may have a contributory role in FP caused by type F c-cpe strains that carry the nanH and nanJ genes.
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Affiliation(s)
- Jihong Li
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Arhat Pradhan
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Bruce A. McClane
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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Cavaiuolo M, Lefebvre D, Mutel I, Vingadassalon N, Merda D, Hennekinne JA, Nia Y. First report of enterotoxigenic Staphylococcus argenteus as a foodborne pathogen. Int J Food Microbiol 2023; 394:110182. [PMID: 36965358 DOI: 10.1016/j.ijfoodmicro.2023.110182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Revised: 03/07/2023] [Accepted: 03/13/2023] [Indexed: 03/19/2023]
Abstract
Staphylococcal enterotoxins preformed in food are the causative agents of staphylococcal food poisoning outbreaks (SFPO). In this study we characterised in depth two coagulase-positive non-pigmented staphylococci involved in two independent outbreaks that occurred in France. While indistinguishable from Staphylococcus aureus using PCR methods and growth phenotype comparisons, both isolates were identified as Staphylococcus argenteus by whole genome sequencing. The genomes were analysed for the presence of enterotoxin genes, whose expression was determined in laboratory medium and, for the first time, in artificially-contaminated milk samples by using liquid chromatography-mass spectrometry and ELISA methods. The concentration measured for the SEB toxin in milk (0.67 ng/ml) was comparable to concentrations reported for other types of enterotoxins behind SFPO. From a collection of publicly available genomes, we performed an unprecedented systematic investigation of the enterotoxin gene set of S. argenteus, including variants and pseudogenes. The most prevalent genes were sex, followed by sel26, sel27 and sey. The egc cluster was less frequent and most of the time carried a dysfunctional seg gene. Our results shed light on the enterotoxigenic properties of S. argenteus, and emphasize the importance in monitoring of S. argenteus as an emerging foodborne pathogen.
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Affiliation(s)
- Marina Cavaiuolo
- University Paris Est, ANSES, Laboratory for Food Safety, SBCL Unit, Maisons-Alfort location, F-94701 Maisons-Alfort, France.
| | - Donatien Lefebvre
- University Paris Est, ANSES, Laboratory for Food Safety, SBCL Unit, Maisons-Alfort location, F-94701 Maisons-Alfort, France
| | - Isabelle Mutel
- University Paris Est, ANSES, Laboratory for Food Safety, SBCL Unit, Maisons-Alfort location, F-94701 Maisons-Alfort, France
| | - Noémie Vingadassalon
- University Paris Est, ANSES, Laboratory for Food Safety, SBCL Unit, Maisons-Alfort location, F-94701 Maisons-Alfort, France
| | - Déborah Merda
- University Paris Est, ANSES, SPAAD unit, Maisons-Alfort location, F-94701 Maisons-Alfort, France
| | - Jacques-Antoine Hennekinne
- University Paris Est, ANSES, Laboratory for Food Safety, SBCL Unit, Maisons-Alfort location, F-94701 Maisons-Alfort, France
| | - Yacine Nia
- University Paris Est, ANSES, Laboratory for Food Safety, SBCL Unit, Maisons-Alfort location, F-94701 Maisons-Alfort, France
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Mehdizadeh Gohari I, Li J, Navarro MA, Mendonça FS, Uzal FA, McClane BA. Identification of orphan histidine kinases that impact sporulation and enterotoxin production by Clostridium perfringens type F strain SM101 in a pathophysiologically-relevant ex vivo mouse intestinal contents model. PLoS Pathog 2023; 19:e1011429. [PMID: 37262083 PMCID: PMC10263361 DOI: 10.1371/journal.ppat.1011429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 06/13/2023] [Accepted: 05/17/2023] [Indexed: 06/03/2023] Open
Abstract
When causing food poisoning or antibiotic-associated diarrhea, Clostridium perfringens type F strains must sporulate to produce C. perfringens enterotoxin (CPE) in the intestines. C. perfringens is thought to use some of its seven annotated orphan histidine kinases to phosphorylate Spo0A and initiate sporulation and CPE production. We previously demonstrated the CPR0195 orphan kinase, but not the putative CPR1055 orphan kinase, is important when type F strain SM101 initiates sporulation and CPE production in modified Duncan-Strong (MDS) sporulation medium. Since there is no small animal model for C. perfringens sporulation, the current study used diluted mouse intestinal contents (MIC) to develop an ex vivo sporulation model and employed this model to test sporulation and CPE production by SM101 CPR0195 and CPR1055 null mutants in a pathophysiologically-relevant context. Surprisingly, both mutants still sporulated and produced CPE at wild-type levels in MIC. Therefore, five single null mutants were constructed that cannot produce one of the previously-unstudied putative orphan kinases of SM101. Those mutants implicated CPR1316, CPR1493, CPR1953 and CPR1954 in sporulation and CPE production by SM101 MDS cultures. Phosphorylation activity was necessary for CPR1316, CPR1493, CPR1953 and CPR1954 to affect sporulation in those MDS cultures, supporting their identity as kinases. Importantly, only the CPR1953 or CPR1954 null mutants exhibited significantly reduced levels of sporulation and CPE production in MIC cultures. These phenotypes were reversible by complementation. Characterization studies suggested that, in MDS or MIC, the CPR1953 and CPR1954 mutants produce less Spo0A than wild-type SM101. In addition, the CPR1954 mutant exhibited little or no Spo0A phosphorylation in MDS cultures. These studies, i) highlight the importance of using pathophysiologically-relevant models to investigate C. perfringens sporulation and CPE production in a disease context and ii) link the CPR1953 and CPR1954 kinases to C. perfringens sporulation and CPE production in disease-relevant conditions.
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Affiliation(s)
- Iman Mehdizadeh Gohari
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Jihong Li
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Mauricio A. Navarro
- California Animal Health and Food Safety Laboratory System, School of Veterinary Medicine, University of California Davis, San Bernardino, California, United States of America
| | - Fábio S. Mendonça
- California Animal Health and Food Safety Laboratory System, School of Veterinary Medicine, University of California Davis, San Bernardino, California, United States of America
| | - Francisco A. Uzal
- California Animal Health and Food Safety Laboratory System, School of Veterinary Medicine, University of California Davis, San Bernardino, California, United States of America
| | - Bruce A. McClane
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
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Nadiya S, Kolla HB, Reddy PN. Optimization and evaluation of a multiplex PCR assay for detection of Staphylococcus aureus and its major virulence genes for assessing food safety. Braz J Microbiol 2023; 54:311-321. [PMID: 36690906 PMCID: PMC9944222 DOI: 10.1007/s42770-023-00906-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Accepted: 01/15/2023] [Indexed: 01/25/2023] Open
Abstract
Staphylococcus aureus is a natural commensal microflora of humans which causes opportunistic infections due to its large arsenal of exotoxins, invasion, immune evasion, and antibiotic resistance mechanisms. The primary goal of this study is to develop a multiplex PCR (mPCR) assay for simultaneous detection of Staphylococcus aureus (nuc) and its virulence genes coding for prominent exotoxins namely alpha hemolysin (hla), enterotoxins A (sea), enterotoxin B (seb), toxic shock syndrome toxin (tsst-1), and the gene coding for methicillin resistance (mecA). A competitive internal amplification control (IAC) was included in the assay to exclude the false negative outcomes. Highly specific primer pairs were designed for the target genes using in silico resources. At the outset, monoplex PCRs were standardized using reference S. aureus strains. Primer specificity to the target genes was authenticated through restriction digestion analysis of amplified PCR products. Multiplex PCR was optimized in increments of one gene starting with nuc and IAC amplified simultaneously using one pair of primers (nuc) in a competitive manner. The mPCR assay was found to be highly sensitive with a detection limit of ~10 CFUs per reaction for pure cultures. Multiplex PCR assay was further evaluated on the retail and processed food samples to test the prevalence of S. aureus and study their exotoxin profiles. Of the 57 samples examined, 13 samples (22.80%) were found to be contaminated with S. aureus whose DNA was extracted after a 6-h enrichment period. Among these, a high percentage of hemolytic and enterotoxin A positive strains were encountered. The mPCR assay developed in this study would be a useful tool for rapid and reliable monitoring of S. aureus for food quality testing and from clinical infections.
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Affiliation(s)
- Shaik Nadiya
- Department of Biotechnology, Vignan's Foundation for Science, Technology and Research (Deemed to be University), Vadlamudi, Andhra Pradesh, Guntur district, 522 213, India
| | - Harish Babu Kolla
- Department of Biotechnology, Vignan's Foundation for Science, Technology and Research (Deemed to be University), Vadlamudi, Andhra Pradesh, Guntur district, 522 213, India
| | - Prakash Narayana Reddy
- Department of Microbiology, Dr. V.S. Krishna Government Degree College (Autonomous), Maddilapalem, Visakhapatnam, Andhra Pradesh, 530 013, India.
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Goto M, Yoshino S, Hiroshima K, Kawakami T, Murota K, Shimamoto S, Hidaka Y. The Molecular Basis of Heat-Stable Enterotoxin for Vaccine Development and Cancer Cell Detection. Molecules 2023; 28:molecules28031128. [PMID: 36770798 PMCID: PMC9920858 DOI: 10.3390/molecules28031128] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 01/19/2023] [Accepted: 01/20/2023] [Indexed: 01/24/2023] Open
Abstract
Heat-stable enterotoxin (STa) produced by Enterotoxigenic E. coli is responsible for causing acute diarrhea in infants in developing countries. However, the chemical synthesis of STa peptides with the native conformation and the correct intra-molecular disulfide bonds is a major hurdle for vaccine development. To address this issue, we herein report on the design and preparation of STa analogs and a convenient chemical method for obtaining STa molecules with the correct conformation. To develop an STa vaccine, we focused on a structure in a type II β-turn in the STa molecule and introduced a D-Lys residue as a conjugation site for carrier proteins. In addition, the -Glu-Leu- sequence in the STa molecule was replaced with a -Asp-Val- sequence to decrease the toxic activity of the peptide to make it more amenable for use in vaccinations. To solve several issues associated with the synthesis of STa, such as the formation of non-native disulfide isomers, the native disulfide pairings were regioselectively formed in a stepwise manner. A native form or topological isomer of the designed STa peptide, which possesses a right-handed or a left-handed spiral structure, respectively, were synthesized in high synthetic yields. The conformation of the synthetic STa peptide was also confirmed by CD and NMR spectroscopy. To further utilize the designed STa peptide, it was labeled with fluorescein for fluorescent detection, since recent studies have also focused on the use of STa for detecting cancer cells, such as Caco-2 and T84. The labeled STa peptide was able to specifically and efficiently detect 293T cells expressing the recombinant STa receptor (GC-C) protein and Caco-2 cells. The findings reported here provide an outline of the molecular basis for using STa for vaccine development and in the detection of cancer cells.
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Affiliation(s)
- Masaya Goto
- Faculty of Science and Engineering, Kindai University, 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502, Japan
| | - Shinya Yoshino
- Faculty of Science and Engineering, Kindai University, 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502, Japan
| | - Kyona Hiroshima
- Faculty of Science and Engineering, Kindai University, 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502, Japan
| | - Toru Kawakami
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Kaeko Murota
- Faculty of Life and Environmental Sciences, Shimane University, 1060 Nishikawatsu, Matsue, Shimane 690-8504, Japan
| | - Shigeru Shimamoto
- Faculty of Science and Engineering, Kindai University, 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502, Japan
- Correspondence: (S.S.); (Y.H.); Tel.: +81-6-6721-2332 (S.S.)
| | - Yuji Hidaka
- Faculty of Science and Engineering, Kindai University, 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502, Japan
- Correspondence: (S.S.); (Y.H.); Tel.: +81-6-6721-2332 (S.S.)
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45
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Yin C, Song Z, Wang X, Li H, Liu Y, Wang Q, Feng X, Song X. Development and clinical application of a rapid, visually interpretable polymerase spiral reaction for tcdB gene of Clostridioides difficile in fecal cultures. FEMS Microbiol Lett 2023; 370:fnad080. [PMID: 37537148 DOI: 10.1093/femsle/fnad080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 06/14/2023] [Accepted: 08/02/2023] [Indexed: 08/05/2023] Open
Abstract
In the surveillance of outbreaks of Clostridioides difficile infection, the rapid detection and diagnosis of C. difficile remain a major challenge. Polymerase spiral reaction (PSR) is a nucleic acid amplification technique that uses mixed primers and the strand displacement activity of Bst DNA polymerase to achieve a pair of primers and a single enzyme in an isothermal environment. The primer design is simple, the reaction is efficient, and a color indicator can be used to visualize the result. In this study, we developed a rapid and visually interpretable PSR to detect C. difficile by analyzing artificially contaminated feces samples and clinical isolates from patient feces samples. We designed two pairs of primers for a PSR that specifically targeted the conserved tcdB gene of C. difficile. The amplification results were visualized with the chromogenic dye hydroxynaphthol blue. The entire process was accomplished in 50 min at 64°C, with high specificity. The limit of detection of C. difficile with PSR was 150 fg/μl genomic DNA or 2 × 10 CFU/ml in artificially contaminated feces samples. With this method, we analyzed four clinical isolates and also compared the PSR with an isolation-and-culture detection method, polymerase chain reaction, and the Sanger sequencing. The four clinical isolates were found positive for tcdB, which confirmed the high specificity of the primers. The positive rates of tcdB in toxigenic C. difficile detected with PSR, PCR, and Sanger sequencing were 100%. The proportions of toxin types in these clinical C. difficile strains were 50% tcdA+tcdB+CDT- and 50% tcdA+tcdB+CDT+. The assay described should extend our understanding of the incidence of C. difficile. This may allow the rapid diagnosis and screening of C. difficile-related disease outbreaks in the field.
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Affiliation(s)
- Caihong Yin
- Department of Hygienic Inspection, School of Public Health, Jilin University, 1163 Xinmin Street, Changchun 130021, China
| | - Zhanyun Song
- Changchun Customs Technology Center, 4448 Freedom Road, Changchun, China
| | - Xianghui Wang
- Changchun Customs Technology Center, 4448 Freedom Road, Changchun, China
| | - Hui Li
- Changchun Customs Technology Center, 4448 Freedom Road, Changchun, China
| | - Yue Liu
- Department of Hygienic Inspection, School of Public Health, Jilin University, 1163 Xinmin Street, Changchun 130021, China
| | - Qiulin Wang
- Department of Hygienic Inspection, School of Public Health, Jilin University, 1163 Xinmin Street, Changchun 130021, China
| | - Xin Feng
- School of Public Health, College of Veterinary Medicine, Jilin University, 5333 Xi 'an Road, Changchun, China
| | - Xiuling Song
- Department of Hygienic Inspection, School of Public Health, Jilin University, 1163 Xinmin Street, Changchun 130021, China
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46
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Singh S, Chowdhury P, Ghosh A, Nara S. Virtual screening of truncated single stranded DNA aptamers for Staphylococcal enterotoxin type A. J Biomol Struct Dyn 2023; 41:11862-11871. [PMID: 36597903 DOI: 10.1080/07391102.2022.2164057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 12/24/2022] [Indexed: 01/05/2023]
Abstract
Single stranded DNA (ssDNA)/RNA aptamers, are screened through the labor intensive, iterative Systematic Evolution of Ligand by Exponential Enrichment process (SELEX) method. Complete sequence of screened aptamers never interacts with target or participates in final structure. Hence, in silico tools can be used to redesign a short length aptamer from previously reported aptamers which can have high affinity and specificity to the target. This approach is fast, cost effective, and less laborious than in vitro SELEX towards finding an aptamer sequence with better affinity with the target. Here, Staphylococcal enterotoxin type A (SEA) was used as target. A total of nine aptamers reported for different Staphylococcal food poisoning (SFP) enterotoxins were used as a starting pool. The aptamers were variously truncations and thoroughly analyzed through in silico methods. Three truncated aptamers namely AptSEA1.4, AptSEA2.4 and AptSEA8.4 were found to show higher affinity with target SEA. The computational data was also validated with DOT BLOT assay complemented with image analysis. These results also confirmed that the % specific binding and the dissociation constant (Kd) of truncated aptamers AptSEA1.4, AptSEA2.4 and AptSEA8.4 was better than their original counterparts. The truncated aptamers showed great promise to be used as a capture reagent in developing a sensitive assay for detection of SEA.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Smriti Singh
- Department of Biotechnology, Motilal Nehru National Institute of Technology Allahabad, Prayagraj, Uttar Pradesh, India
| | - Papia Chowdhury
- Department of Physics and Material Science, Jaypee Institute of Information Technology, Noida, Uttar Pradesh, India
| | - Arabinda Ghosh
- Microbiology Division, Department of Botany, Guwahati University, Guwahati, Assam, India
| | - Seema Nara
- Department of Biotechnology, Motilal Nehru National Institute of Technology Allahabad, Prayagraj, Uttar Pradesh, India
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47
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Xu C, Peng K, She Y, Fu F, Shi Q, Lin Y, Xu C. Preparation of novel trivalent vaccine against enterotoxigenic Escherichia coli for preventing newborn piglet diarrhea. Am J Vet Res 2023; 84:ajvr.22.10.0183. [PMID: 36576801 DOI: 10.2460/ajvr.22.10.0183] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
OBJECTIVE To develop a trivalent genetically engineered inactivated Escherichia coli vaccine (K88ac-3STa-LTB) that neutralizes the STa toxin by targeting fimbriae and entertoxins for the treatment of enterotoxigenic E coli. ANIMALS 18- to 22-g mice, rabbits, pregnant sows. PROCEDURES Using PCR, the K88ac gene and LTB gene were cloned separately from the template C83902 plasmid. At the same time, the 3 STa mutant genes were also amplified by using the gene-directed mutation technology. Immune protection experiments were performed, and the minimum immune dose was determined in mice and pregnant sows. RESULTS The ELISA test could be recognized by the STa, LTB, and K88ac antibodies. Intragastric administration in the suckling mouse confirmed that the protein had lost the toxicity of the natural STa enterotoxin. The results of the immune experiments showed that K88ac-3STa-LTB protein could stimulate rabbits to produce serum antibodies and neutralize the toxicity of natural STa enterotoxin. The efficacy test of the K88ac-3STa-LTB-inactivated vaccine showed that the immune protection rate of the newborn piglets could reach 85% on the first day after suckling. At the same time, it was determined that the minimum immunization doses for mice and pregnant sows were 0.2 and 2.5 mL, respectively. CLINICAL RELEVANCE This research indicates that the K88ac-3STa-LTB trivalent genetically engineered inactivated vaccine provides a broad immune spectrum for E coli diarrhea in newborn piglets and prepares a new genetically engineered vaccine candidate strain for prevention of E coli diarrhea in piglets.
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Affiliation(s)
- ChongLi Xu
- College of Medical Technology, Chongqing Medical and Pharmaceutical College, Chongqing, People's Republic of China
| | - Kun Peng
- College of Medical Technology, Chongqing Medical and Pharmaceutical College, Chongqing, People's Republic of China
| | - Yuhan She
- College of Medical Technology, Chongqing Medical and Pharmaceutical College, Chongqing, People's Republic of China
| | - Fengyang Fu
- College of Medical Technology, Chongqing Medical and Pharmaceutical College, Chongqing, People's Republic of China
| | - Qinhong Shi
- College of Medical Technology, Chongqing Medical and Pharmaceutical College, Chongqing, People's Republic of China
| | - Yimin Lin
- Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment, Chongqing University Cancer Hospital, Chongqing, People's Republic of China
| | - ChongBo Xu
- Henry Fok College of Biology and Agriculture, Shaoguan University, Shaoguan, People's Republic of China
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48
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Crivaro AN, Carasi P, Salto I, Hugo A, Soldavini Pelichotti PC, Bengoa A, Fragomeno M, Serradell MA, Minnaard J, Rolny I, Alul E, Arregui L, Fabra Martinez ME, Moreno Valero OJ, Facente A, Magariños F, Jewtuchowicz V, Pérez PF, Trejo FM. Clostridioides difficile: Characterization of the circulating toxinotypes in an Argentinean public hospital. Rev Argent Microbiol 2023; 55:73-82. [PMID: 35840437 DOI: 10.1016/j.ram.2022.05.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 02/22/2022] [Accepted: 05/02/2022] [Indexed: 02/07/2023] Open
Abstract
Clostridioides difficile is a spore-forming anaerobe microorganism associated to nosocomial diarrhea. Its virulence is mainly associated with TcdA and TcdB toxins, encoded by their respective tcdA and tcdB genes. These genes are part of the pathogenicity locus (PaLoc). Our aim was to characterize relevant C. difficile toxinotypes circulating in the hospital setting. The tcdA and tcdB genes were amplified and digested with different restriction enzymes: EcoRI for tcdA; HincII and AccI for tcdB. In addition, the presence of the cdtB (binary toxin) gene, TcdA and TcdB toxins by dot blot and the cytotoxic effect of culture supernatants on Vero cells, were evaluated. Altogether, these studies revealed three different circulating toxinotypes according to Rupnik's classification: 0, I and VIII, being the latter the most prevalent one. Even though more studies are certainly necessary (e.g. sequencing analysis), it is worth noting that the occurrence of toxinotype I could be related to the introduction of bacteria from different geographical origins. The multivariate analysis conducted on the laboratory values of individuals infected with the most prevalent toxinotype (VIII) showed that the isolates associated with fatal outcomes (GCD13, GCD14 and GCD22) are located in regions of the biplots related to altered laboratory values at admission. In other patients, although laboratory values at admission were not correlated, levels of urea, creatinine and white blood cells were positively correlated after the infection was diagnosed. Our study reveals the circulation of different toxinotypes of C. difficile strains in this public hospital. The variety of toxinotypes can arise from pre-existing microorganisms as well as through the introduction of bacteria from other geographical regions. The existence of microorganisms with different pathogenic potential is relevant for the control, follow-up, and treatment of the infections.
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Affiliation(s)
- Andrea N Crivaro
- Cátedra de Microbiología, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calle 47 y 115, B1900AJI La Plata, Argentina; IIFP, Universidad Nacional de La Plata, CONICET, Facultad de Ciencias Exactas, Departamento de Ciencias Biológicas, La Plata, Argentina
| | - Paula Carasi
- IIFP, Universidad Nacional de La Plata, CONICET, Facultad de Ciencias Exactas, Departamento de Ciencias Biológicas, La Plata, Argentina
| | - Ileana Salto
- Cátedra de Microbiología, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calle 47 y 115, B1900AJI La Plata, Argentina; IBBM (Instituto de Biotecnología y Biología Molecular), CCT-CONICET-La Plata, Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calles 47 y 115 (1900), La Plata, Argentina
| | - Ayelen Hugo
- Centro de Investigación y Desarrollo en Criotecnología de Alimentos, CCT La Plata, CONICET-UNLP-CIC PBA, 47 y 116 (s/n), La Plata 1900, Argentina
| | - P Cecilia Soldavini Pelichotti
- Cátedra de Microbiología, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calle 47 y 115, B1900AJI La Plata, Argentina; Centro de Investigación y Desarrollo en Criotecnología de Alimentos, CCT La Plata, CONICET-UNLP-CIC PBA, 47 y 116 (s/n), La Plata 1900, Argentina
| | - Agustina Bengoa
- Centro de Investigación y Desarrollo en Criotecnología de Alimentos, CCT La Plata, CONICET-UNLP-CIC PBA, 47 y 116 (s/n), La Plata 1900, Argentina
| | - Melisa Fragomeno
- Centro de Investigación y Desarrollo en Criotecnología de Alimentos, CCT La Plata, CONICET-UNLP-CIC PBA, 47 y 116 (s/n), La Plata 1900, Argentina
| | - María A Serradell
- Cátedra de Microbiología, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calle 47 y 115, B1900AJI La Plata, Argentina
| | - Jessica Minnaard
- Cátedra de Microbiología, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calle 47 y 115, B1900AJI La Plata, Argentina; Centro de Investigación y Desarrollo en Criotecnología de Alimentos, CCT La Plata, CONICET-UNLP-CIC PBA, 47 y 116 (s/n), La Plata 1900, Argentina
| | - Ivanna Rolny
- Cátedra de Microbiología, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calle 47 y 115, B1900AJI La Plata, Argentina; IIFP, Universidad Nacional de La Plata, CONICET, Facultad de Ciencias Exactas, Departamento de Ciencias Biológicas, La Plata, Argentina
| | - Eduardo Alul
- Luisa G de Gandulfo Hospital, Lomas de Zamora, Buenos Aires, Argentina
| | - Leandro Arregui
- Luisa G de Gandulfo Hospital, Lomas de Zamora, Buenos Aires, Argentina
| | | | | | - Andrea Facente
- Luisa G de Gandulfo Hospital, Lomas de Zamora, Buenos Aires, Argentina
| | | | | | - Pablo F Pérez
- Cátedra de Microbiología, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calle 47 y 115, B1900AJI La Plata, Argentina; Centro de Investigación y Desarrollo en Criotecnología de Alimentos, CCT La Plata, CONICET-UNLP-CIC PBA, 47 y 116 (s/n), La Plata 1900, Argentina.
| | - Fernando M Trejo
- Centro de Investigación y Desarrollo en Criotecnología de Alimentos, CCT La Plata, CONICET-UNLP-CIC PBA, 47 y 116 (s/n), La Plata 1900, Argentina
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49
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Blicharz L, Żochowski M, Szymanek-Majchrzak K, Czuwara J, Goldust M, Skowroński K, Młynarczyk G, Olszewska M, Samochocki Z, Rudnicka L. Enterotoxin Gene Cluster and selX Are Associated with Atopic Dermatitis Severity-A Cross-Sectional Molecular Study of Staphylococcus aureus Superantigens. Cells 2022; 11:cells11233921. [PMID: 36497178 PMCID: PMC9737390 DOI: 10.3390/cells11233921] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 11/17/2022] [Accepted: 11/29/2022] [Indexed: 12/12/2022] Open
Abstract
Staphylococcus aureus superantigens (SAgs) have been reported to aggravate atopic dermatitis. However, comprehensive analyses of these molecules in multiple microniches are lacking. The present study involved 50 adult patients with active atopic dermatitis. S. aureus was isolated from the lesional skin, nonlesional skin, and anterior nares. Multiplex-PCR was performed to identify genes encoding (1) selX (core genome); (2) seg, selI, selM, selN, selO, selU (enterotoxin gene cluster, EGC); and (3) sea, seb, sec, sed, see, tstH (classic SAgs encoded on other mobile genetic elements). The results were correlated to clinical parameters of the study group. selx and EGC were the most prevalent in all microniches. The number of SAg-encoding genes correlated between the anterior nares and nonlesional skin, and between the nonlesional and lesional skin. On lesional skin, the total number of SAg genes correlated with disease severity (total and objective SCORAD, intensity, erythema, edema/papulation, lichenification and dryness). Linear regression revealed that AD severity was predicted only by selx and EGC. This study revealed that selX and EGC are associated with atopic dermatitis severity. Anterior nares and nonlesional skin could be reservoirs of SAg-positive S. aureus. Restoring the physiological microbiome could reduce the SAg burden and alleviate syndromes of atopic dermatitis.
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Affiliation(s)
- Leszek Blicharz
- Department of Dermatology, Medial University of Warsaw, 02-008 Warsaw, Poland
| | - Maciej Żochowski
- Department of Dermatology, Medial University of Warsaw, 02-008 Warsaw, Poland
| | | | - Joanna Czuwara
- Department of Dermatology, Medial University of Warsaw, 02-008 Warsaw, Poland
- Correspondence:
| | - Mohamad Goldust
- Department of Dermatology, Yale School of Medicine, Yale University, New Haven, CT 06519, USA
| | | | - Grażyna Młynarczyk
- Department of Medical Microbiology, Medial University of Warsaw, 02-004 Warsaw, Poland
| | | | - Zbigniew Samochocki
- Department of Dermatology, Medial University of Warsaw, 02-008 Warsaw, Poland
| | - Lidia Rudnicka
- Department of Dermatology, Medial University of Warsaw, 02-008 Warsaw, Poland
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50
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Sheikh A, Tumala B, Vickers TJ, Martin JC, Rosa BA, Sabui S, Basu S, Simoes RD, Mitreva M, Storer C, Tyksen E, Head RD, Beatty W, Said HM, Fleckenstein JM. Enterotoxigenic Escherichia coli heat-labile toxin drives enteropathic changes in small intestinal epithelia. Nat Commun 2022; 13:6886. [PMID: 36371425 PMCID: PMC9653437 DOI: 10.1038/s41467-022-34687-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 11/01/2022] [Indexed: 11/14/2022] Open
Abstract
Enterotoxigenic E. coli (ETEC) produce heat-labile (LT) and/or heat-stable (ST) enterotoxins, and commonly cause diarrhea in resource-poor regions. ETEC have been linked repeatedly to sequelae in children including enteropathy, malnutrition, and growth impairment. Although cellular actions of ETEC enterotoxins leading to diarrhea are well-established, their contributions to sequelae remain unclear. LT increases cellular cAMP to activate protein kinase A (PKA) that phosphorylates ion channels driving intestinal export of salt and water resulting in diarrhea. As PKA also modulates transcription of many genes, we interrogated transcriptional profiles of LT-treated intestinal epithelia. Here we show that LT significantly alters intestinal epithelial gene expression directing biogenesis of the brush border, the major site for nutrient absorption, suppresses transcription factors HNF4 and SMAD4 critical to enterocyte differentiation, and profoundly disrupts microvillus architecture and essential nutrient transport. In addition, ETEC-challenged neonatal mice exhibit substantial brush border derangement that is prevented by maternal vaccination with LT. Finally, mice repeatedly challenged with toxigenic ETEC exhibit impaired growth recapitulating the multiplicative impact of recurring ETEC infections in children. These findings highlight impacts of ETEC enterotoxins beyond acute diarrheal illness and may inform approaches to prevent major sequelae of these common infections including malnutrition that impact millions of children.
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Affiliation(s)
- Alaullah Sheikh
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Brunda Tumala
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Tim J Vickers
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - John C Martin
- The McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Bruce A Rosa
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
- The McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Subrata Sabui
- Departments of Medicine and Physiology/Biophysics, School of Medicine, University of California-Irvine, Irvine, CA, 92697, USA
- Department of Research, VA Medical Center, Long Beach, CA, 90822, USA
| | - Supratim Basu
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Rita D Simoes
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Makedonka Mitreva
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
- The McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Chad Storer
- The McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, 63110, USA
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Erik Tyksen
- The McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, 63110, USA
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Richard D Head
- The McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, 63110, USA
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Wandy Beatty
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO, 63110, USA
| | - Hamid M Said
- Departments of Medicine and Physiology/Biophysics, School of Medicine, University of California-Irvine, Irvine, CA, 92697, USA
- Department of Research, VA Medical Center, Long Beach, CA, 90822, USA
| | - James M Fleckenstein
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA.
- Infectious Diseases, Medicine Service, Veterans Affairs Saint Louis Health Care System, Saint Louis, MO, 63106, USA.
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