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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] [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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Molecular Typing, Antibiotic Resistance and Enterotoxin Gene Profiles of Staphylococcus aureus Isolated from Humans in South Korea. Microorganisms 2022; 10:microorganisms10030642. [PMID: 35336216 PMCID: PMC8952563 DOI: 10.3390/microorganisms10030642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Revised: 03/12/2022] [Accepted: 03/15/2022] [Indexed: 11/17/2022] Open
Abstract
The emergence of antimicrobial-resistant Staphylococcus aureus has become a grave concern worldwide. In this study, 95 strains of S. aureus isolated from stool samples were collected from Busan, South Korea to characterize their antimicrobial susceptibility, enterotoxin genes, and molecular typing using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and random amplification of polymorphic DNA (RAPD) assay. Only two strains showed no drug resistance, whereas resistance to three or more antibiotics was observed in 87.4% of strains. Ampicillin resistance was the most common at 90% and all strains were susceptible to vancomycin. The distribution of enterotoxin genes encoded in isolates was sea (32.6%), sec (11.6%), seg (19%), sea & sec (2.1%), and sec & seg (34.7%). Molecular typing using both MALDI-TOF MS and RAPD indicated that S. aureus exhibited diverse clonal lineages and no correlations were observed among the profiling of enterotoxin, MALDI-TOF MS, and RAPD. This investigation provides useful information on foodborne pathogenic S. aureus that has a significant public health impact in South Korea.
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Singh C, Upadhyay R, Tiwari KN. Comparative analysis of the seasonal influence on polyphenolic content, antioxidant capacity, identification of bioactive constituents and hepatoprotective biomarkers by in silico docking analysis in Premna integrifolia L. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2022; 28:223-249. [PMID: 35221581 PMCID: PMC8847619 DOI: 10.1007/s12298-021-01120-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 12/17/2021] [Accepted: 12/17/2021] [Indexed: 06/14/2023]
Abstract
The present study reports the effect of different seasons on polyphenol content and antioxidant potential of ethanolic, methanolic, ethyl acetate, and aqueous extracts of leaves, stems, and roots of Premna integrifolia. Ethyl acetate extract of leaves (EAEPI) collected in the rainy season showed potent antioxidant activity with highest total phenol (74.33 ± 2.26 µg/mg, gallic acid equivalent), and flavonoid (98.83 ± 0.26 µg/mg, rutin equivalent) content. Therefore, EAEPI extract was subjected to characterization by UHPLC-Q-TOF-MS/MS and GC-MS analysis for the identification of active constituents. UHPLC-Q-TOF-MS/MS analysis in + ve ion mode revealed the presence of eight polyphenolic compounds namely quercetin-3-D-xyloside, kaempferol-3,7-O-bis-alpha-L-rhamnoside, isorhamnetin-3-Oglucoside, luteolin-3',7-di-O-glucoside, eriodictyol-7-O-glucoside, syringetin-3-O-galactoside, petunidin-3-O-beta-glucopyranoside and vitexin-2″-O-rhamnoside. GC-MS analysis confirmed the presence of 26 compounds with six major compounds viz; citronellol, phytol acetate, campesterol, squalene, stigmasterol, and hexadecanoic acid. These compounds are reported for the first time from P. integrifolia except phytol and stigmasterol. Our previous study validates the hepatoprotective potential of P. integrifolia but there was no idea about the bioactive compound responsible for the activity. So, in present work, the major compounds identified in spectrometry analysis were subjected to in silico docking against an important liver enzyme alanine amino transaminase to confirm its hepatoprotective properties. Docking analysis validates the presence of two hepatoprotective lead compounds stigmasterol, and campesterol, which satisfy the drug-likeness criteria with good absorption, distribution, metabolism, and toxicity properties. Thus, present work gives a clear insight about the influence of season on the total polyphenolic constituent in different plant parts of P. integrifolia, their antioxidant potential and preclinical evaluation of hepatoprotective lead compounds.
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Affiliation(s)
- Chandrashekhar Singh
- Department of Botany, MMV, Banaras Hindu University, Varanasi, Uttar Pradesh 221005 India
| | - Richa Upadhyay
- Department of Botany, Mihir Bhoj Postgraduate College, G.B. Nagar, Dadri, Uttar Pradesh 203207 India
| | - Kavindra Nath Tiwari
- Department of Botany, MMV, Banaras Hindu University, Varanasi, Uttar Pradesh 221005 India
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Yu SH, Lee JH, Kim MC, Choi SH, Chung JW, Lee MK. Ten-Year Prevalence Trends of Phenotypically Identified Community-Associated Methicillin-Resistant Staphylococcus aureus Strains in Clinical Specimens. Ann Lab Med 2021; 41:386-393. [PMID: 33536357 PMCID: PMC7884191 DOI: 10.3343/alm.2021.41.4.386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Background Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) strains were first detected in hospitals in Korea between the late 2000s and early 2010s. However, there is limited information regarding the prevalence of CA-MRSA strains among hospital isolates and their phenotypic changes over the last decade. We investigated the prevalence trend of CA-MRSA strains isolated from different clinical specimens and their phenotypic changes between September 2009 and September 2019. Methods CA-MRSA strains were phenotypically identified by confirming their resistance to penicillin (PCN) and oxacillin (OXA) and evaluating their susceptibility to trimethoprim-sulfamethoxazole, rifampin, fusidic acid, tetracycline, and at least one of the following four antimicrobials: clindamycin (CLI), erythromycin (ERY), ciprofloxacin (CIP), and gentamicin (GEN). A CA-MRSA strain that exhibited resistance to ERY, CLI, CIP, or GEN was classified as having resistance pattern I, II, III, or IV, respectively, regardless of its resistance to other antimicrobial agents. Results Of the 8,278 MRSA isolates identified in specimens obtained two days after admission, 1,385 (16.73%) were CA-MRSA strains. The prevalence of CA-MRSA strains increased from 12.2% to 26.6% (3.21% per period, P=0.05). Resistance type analysis revealed an increasing trend in the prevalence of PCN/OXA-resistant (1.84%; P=0.049) and PCN/OXA/ERY/CLI/CIP-resistant (0.98%; P=0.04) CA-MRSA strains and in resistance pattern III strains (2.08%; P=0.004). Conclusions The prevalence of CA-MRSA strains in Korea has increased significantly over the last decade, and CA-MRSA strains have gained phenotypic diversity beyond PCN/OXA-resistance, including antimicrobial resistance to non-β-lactams, especially CIP.
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Affiliation(s)
- So Hyun Yu
- Chung-Ang University College of Medicine, Seoul, Korea
| | | | - Min-Chul Kim
- Chung-Ang University College of Medicine, Seoul, Korea.,Division of Infectious Diseases, Department of Internal Medicine, Chung-Ang University Hospital, Seoul, Korea
| | - Seong-Ho Choi
- Chung-Ang University College of Medicine, Seoul, Korea.,Division of Infectious Diseases, Department of Internal Medicine, Chung-Ang University Hospital, Seoul, Korea
| | - Jin-Won Chung
- Chung-Ang University College of Medicine, Seoul, Korea.,Division of Infectious Diseases, Department of Internal Medicine, Chung-Ang University Hospital, Seoul, Korea
| | - Mi-Kyung Lee
- Chung-Ang University College of Medicine, Seoul, Korea.,Department of Laboratory Medicine, Chung-Ang University Hospital, Seoul, Korea
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Machado V, Pardo L, Cuello D, Giudice G, Luna PC, Varela G, Camou T, Schelotto F. Presence of genes encoding enterotoxins in Staphylococcus aureus isolates recovered from food, food establishment surfaces and cases of foodborne diseases. Rev Inst Med Trop Sao Paulo 2020; 62:e5. [PMID: 32049256 PMCID: PMC7014549 DOI: 10.1590/s1678-9946202062005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 12/06/2019] [Indexed: 11/22/2022] Open
Abstract
The aim of this study was to describe the microbiological characteristics and profile of genes encoding enterotoxins in 95 Staphylococcus aureus isolates obtained between April 2011 and December 2014 from foodstuffs, persons and surfaces of retail food stores. After microbiological identification and antimicrobial susceptibility testing, polymerase chain reactions (PCR) were performed, targeting sea, seb, sec, sed and see genes that code for classical enterotoxins (ET) A-E, and three additional genes: seg , seh and sei , coding for so-called "new enterotoxins" G, H and I. The isolates were characterized by Pulsed Field Gel Electrophoresis (PFGE), and five selected isolates were further analyzed through Multi Locus Sequence Typing (MLST). It is noteworthy that 54.7% of the examined isolates harbored one or more of the investigated ET gene types. Most positive isolates carried more than one ET gene up to five types; seg was the most frequent ET gene, followed by sei. Five enterotoxin-coding isolates also coded for some antimicrobial resistance genes. Two of them, and four additional non-enterotoxic isolates carried erm genes expressing inducible clindamycin resistance. PFGE-types were numerous and diverse, even among enterotoxin-coding strains, because most isolates did not belong to known foodborne outbreaks and the sampling period was long. MLST profiles were also varied, and a new ST 3840 was described within this species. ST 88 and ST 72 enterotoxin-coding isolates have been identified in other regions in association with foodborne outbreaks. This manuscript reports the first systematic investigation of enterotoxin genes in S. aureus isolates obtained from foodstuffs and infected people in Uruguay.
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Affiliation(s)
- Virginia Machado
- Universidad de la República, Facultad de Medicina, Instituto de Higiene, Departamento de Bacteriología y Virología, Montevideo, Uruguay
| | - Lorena Pardo
- Universidad de la República, Facultad de Medicina, Instituto de Higiene, Departamento de Bacteriología y Virología, Montevideo, Uruguay
| | - Dianna Cuello
- Universidad de la República, Facultad de Medicina, Instituto de Higiene, Departamento de Bacteriología y Virología, Montevideo, Uruguay
| | - Guillermina Giudice
- Universidad de la República, Facultad de Medicina, Instituto de Higiene, Departamento de Bacteriología y Virología, Montevideo, Uruguay
| | - Patricia Correa Luna
- Universidad de la República, Facultad de Medicina, Instituto de Higiene, Departamento de Bacteriología y Virología, Montevideo, Uruguay
| | - Gustavo Varela
- Universidad de la República, Facultad de Medicina, Instituto de Higiene, Departamento de Bacteriología y Virología, Montevideo, Uruguay
| | - Teresa Camou
- Departamento de Laboratorios de Salud Pública, Montevideo, Uruguay
| | - Felipe Schelotto
- Universidad de la República, Facultad de Medicina, Instituto de Higiene, Departamento de Bacteriología y Virología, Montevideo, Uruguay
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Tian X, Feng J, Wang Y. Direct loop-mediated isothermal amplification assay for on-site detection of Staphylococcus aureus. FEMS Microbiol Lett 2019; 365:4966978. [PMID: 29648586 PMCID: PMC5967525 DOI: 10.1093/femsle/fny092] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 04/08/2018] [Indexed: 01/13/2023] Open
Abstract
Staphylococcus aureus (S. aureus) is a major human pathogen that may produce a variety of toxins and cause staphylococcal food poisoning. In the present study, a direct loop-mediated isothermal amplification (LAMP) assay was developed and validated to detect S. aureus in food samples. Without prior cultural enrichment and DNA extraction steps, bacterial DNA was released by heating at 100°C for 5 min and directly subjected to LAMP assay. Using a set of LAMP primers recognizing six distinct regions of nuc gene, the developed direct LAMP assay was highly specific, and the analytical sensitivity was determined to be 7.6 × 102 CFU/mL. Moreover, with the pre-mixed LAMP reagents stored at –20°C, the entire assay should be finished within 40 min. These features greatly simplified the operating procedure and made the direct LAMP a powerful tool for rapid and on-site detection of S. aureus in food samples.
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Affiliation(s)
- Xiaolan Tian
- Institute of Seafood, Zhejiang Gongshang University, Hangzhou 310012, PR China
| | - Junli Feng
- Institute of Seafood, Zhejiang Gongshang University, Hangzhou 310012, PR China.,Key Lab of aquatic Products Processing of Zhejiang Province, Hangzhou 310012, PR China
| | - Yi Wang
- Institute of Seafood, Zhejiang Gongshang University, Hangzhou 310012, PR China
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7
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Zi C, Zeng D, Ling N, Dai J, Xue F, Jiang Y, Li B. An improved assay for rapid detection of viable Staphylococcus aureus cells by incorporating surfactant and PMA treatments in qPCR. BMC Microbiol 2018; 18:132. [PMID: 30309323 PMCID: PMC6182795 DOI: 10.1186/s12866-018-1273-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Accepted: 09/27/2018] [Indexed: 11/30/2022] Open
Abstract
Background Staphylococcus aureus is an important human pathogen causing a variety of life-threatening diseases. Rapid and accurate detection of Staphylococcus aureus is a necessity for prevention of outbreaks caused by this pathogen. PCR is a useful tool for rapid detection of foodborne pathogens, however, its inability to differentiate DNA from dead cells and live cells in amplification severely limits its application in pathogen detection. The aim of this study was to develop an improved assay was developed by incorporating the sample treatments with a surfactant and propidium monoazide (PMA) in qPCR for detection of viable S. aureus cells. Results The cell toxic effect testing with the two surfactants showed that the viability of S. aureus was virtually not affected by the treatment with 0.5% triton x-100 or 0.025% sarkosyl. Triton x-100 was coupled with PMA for sample treatments for detection of viable S. aureus cells in artificially contaminated milk. The qPCR results indicated that the assay reached high an amplification efficiency of 98.44% and the live S. aureus cells were accurately detected from the triton-treated spiked milk samples by the PMA-qPCR assay. Conclusions The qPCR assay combined with treatments of PMA and surfactants offers a sensitive and accurate means for detection of viable S. aureus cells. Cell toxic effect testing with the two surfactants showed that the viability of S. aureus was virtually not affected by the treatment with 0.5% triton x-100 or 0.025% sarkosyl. The information on sample treatment with surfactants to improve the dead cell DNA removal efficiency in qPCR by increasing PMA’s permeability to dead cells can be used for other pathogens, especially for Gram-positive bacteria.
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Affiliation(s)
- Chen Zi
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China
| | - Dexin Zeng
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China
| | - Nan Ling
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China
| | - Jianjun Dai
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China
| | - Feng Xue
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China.
| | - Yuan Jiang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China.,Shanghai Entry-Exit Inspection and Quarantine Bureau, Shanghai, 200135, China
| | - Baoguang Li
- Division of Molecular Biology, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, MD, 20708, USA
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Park KH, Choi YJ, Kim J, Park HJ, Song D, Jang WJ. Reclassification of Borrelia spp. Isolated in South Korea Using Multilocus Sequence Typing. Jpn J Infect Dis 2018; 71:350-353. [PMID: 29848848 DOI: 10.7883/yoken.jjid.2018.139] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Here, we used multilocus sequence typing (MLST) to evaluate 3 intergenic genes (16S rRNA, ospA, and 5S-23S IGS) in Borrelia isolated from South Korea to analyze the relationships between host, vector, and molecular background. We identified B. afzelii, B. yangtzensis, B. garinii, and B. bavariensis. This study is the first report for the identification of B. yangtzensis using MLST in South Korea.
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Affiliation(s)
- Kyung-Hee Park
- Department of Microbiology, College of Medicine, Konkuk University
| | - Yeon-Joo Choi
- Department of Microbiology, College of Medicine, Konkuk University.,Institute of Glocal Disease Control, College of Medicine, Konkuk University
| | - Jeoungyeon Kim
- Department of Microbiology, College of Medicine, Konkuk University.,Institute of Glocal Disease Control, College of Medicine, Konkuk University
| | - Hye-Jin Park
- Department of Microbiology, College of Medicine, Konkuk University.,Institute of Glocal Disease Control, College of Medicine, Konkuk University
| | - Dayoung Song
- Department of Microbiology, College of Medicine, Konkuk University.,Institute of Glocal Disease Control, College of Medicine, Konkuk University
| | - Won-Jong Jang
- Department of Microbiology, College of Medicine, Konkuk University.,Institute of Glocal Disease Control, College of Medicine, Konkuk University
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Fisher EL, Otto M, Cheung GYC. Basis of Virulence in Enterotoxin-Mediated Staphylococcal Food Poisoning. Front Microbiol 2018; 9:436. [PMID: 29662470 PMCID: PMC5890119 DOI: 10.3389/fmicb.2018.00436] [Citation(s) in RCA: 145] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 02/26/2018] [Indexed: 12/17/2022] Open
Abstract
The Staphylococcus aureus enterotoxins are a superfamily of secreted virulence factors that share structural and functional similarities and possess potent superantigenic activity causing disruptions in adaptive immunity. The enterotoxins can be separated into two groups; the classical (SEA-SEE) and the newer (SEG-SElY and counting) enterotoxin groups. Many members from both these groups contribute to the pathogenesis of several serious human diseases, including toxic shock syndrome, pneumonia, and sepsis-related infections. Additionally, many members demonstrate emetic activity and are frequently responsible for food poisoning outbreaks. Due to their robust tolerance to denaturing, the enterotoxins retain activity in food contaminated previously with S. aureus. The genes encoding the enterotoxins are found mostly on a variety of different mobile genetic elements. Therefore, the presence of enterotoxins can vary widely among different S. aureus isolates. Additionally, the enterotoxins are regulated by multiple, and often overlapping, regulatory pathways, which are influenced by environmental factors. In this review, we also will focus on the newer enterotoxins (SEG-SElY), which matter for the role of S. aureus as an enteropathogen, and summarize our current knowledge on their prevalence in recent food poisoning outbreaks. Finally, we will review the current literature regarding the key elements that govern the complex regulation of enterotoxins, the molecular mechanisms underlying their enterotoxigenic, superantigenic, and immunomodulatory functions, and discuss how these activities may collectively contribute to the overall manifestation of staphylococcal food poisoning.
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Affiliation(s)
- Emilie L Fisher
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Michael Otto
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Gordon Y C Cheung
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
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10
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Bastos CP, Bassani MT, Mata MM, Lopes GV, da Silva WP. Prevalence and expression of staphylococcal enterotoxin genes in Staphylococcus aureus isolated from food poisoning outbreaks. Can J Microbiol 2017; 63:834-840. [PMID: 28820948 DOI: 10.1139/cjm-2017-0316] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Staphylococcus aureus is an important pathogen of foodborne origin. The pathogen produces a variety of toxins that include the staphylococcal enterotoxins (SE). The present study aimed to evaluate the prevalence and expression of 5 SE genes (sea, seb, sec, sed, and see) in S. aureus isolated from outbreaks occurred in the state of Rio Grande do Sul, Brazil. All isolates, with the exception of 2, presented the same or higher transcriptional expression than the reference strains for at least 1 of these genes. The presence of SE genes combined with high levels of transcriptional expression suggests that 1 or more SEs were involved with the staphylococcal food poisoning outbreak analyzed in the present study.
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Affiliation(s)
- Caroline Peixoto Bastos
- Federal University of Pelotas (UFPel), Faculty of Agronomy Eliseu Maciel (FAEM), Department of Science and Food Technology, Pelotas, RS, Brazil.,Federal University of Pelotas (UFPel), Faculty of Agronomy Eliseu Maciel (FAEM), Department of Science and Food Technology, Pelotas, RS, Brazil
| | - Milena Tomasi Bassani
- Federal University of Pelotas (UFPel), Faculty of Agronomy Eliseu Maciel (FAEM), Department of Science and Food Technology, Pelotas, RS, Brazil.,Federal University of Pelotas (UFPel), Faculty of Agronomy Eliseu Maciel (FAEM), Department of Science and Food Technology, Pelotas, RS, Brazil
| | - Marcia Magalhães Mata
- Federal University of Pelotas (UFPel), Faculty of Agronomy Eliseu Maciel (FAEM), Department of Science and Food Technology, Pelotas, RS, Brazil.,Federal University of Pelotas (UFPel), Faculty of Agronomy Eliseu Maciel (FAEM), Department of Science and Food Technology, Pelotas, RS, Brazil
| | - Graciela Volz Lopes
- Federal University of Pelotas (UFPel), Faculty of Agronomy Eliseu Maciel (FAEM), Department of Science and Food Technology, Pelotas, RS, Brazil.,Federal University of Pelotas (UFPel), Faculty of Agronomy Eliseu Maciel (FAEM), Department of Science and Food Technology, Pelotas, RS, Brazil
| | - Wladimir Padilha da Silva
- Federal University of Pelotas (UFPel), Faculty of Agronomy Eliseu Maciel (FAEM), Department of Science and Food Technology, Pelotas, RS, Brazil.,Federal University of Pelotas (UFPel), Faculty of Agronomy Eliseu Maciel (FAEM), Department of Science and Food Technology, Pelotas, RS, Brazil
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11
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Current methodologies on genotyping for nosocomial pathogen methicillin-resistant Staphylococcus aureus (MRSA). Microb Pathog 2017; 107:17-28. [PMID: 28284852 DOI: 10.1016/j.micpath.2017.03.010] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 03/06/2017] [Accepted: 03/07/2017] [Indexed: 11/23/2022]
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a common pathogen in hospitals and the community. As the rapid spread and wide distribution of antimicrobial resistance (such as MRSA), treatment for infectious diseases caused by microorganisms has become a vital threat. Thus, early identification and genotyping are essential for further therapeutic treatment and the control of rapid expansion of MRSA. In combination with applications and data feedbacks, this review focused on the currently available molecular-based assays on their utility and performance for rapid typing of MRSA, especially on effective molecular-based methods. Besides, a common mobile element SCCmec and prevalence of HA-MRSA, LA-MRSA and CA-MRSA were introduced in this review in order to provide a more complete profile of MRSA.
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Coagulase gene polymorphism of Staphylococcus aureus isolates: A study on dairy food products and other foods in Tehran, Iran. FOOD SCIENCE AND HUMAN WELLNESS 2016. [DOI: 10.1016/j.fshw.2016.09.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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