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Cieza MYR, Bonsaglia ECR, Rall VLM, dos Santos MV, Silva NCC. Staphylococcal Enterotoxins: Description and Importance in Food. Pathogens 2024; 13:676. [PMID: 39204276 PMCID: PMC11357529 DOI: 10.3390/pathogens13080676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2024] [Revised: 07/31/2024] [Accepted: 08/01/2024] [Indexed: 09/03/2024] Open
Abstract
Staphylococcus aureus stands out as one of the most virulent pathogens in the genus Staphylococcus. This characteristic is due to its ability to produce a wide variety of staphylococcal enterotoxins (SEs) and exotoxins, which in turn can cause staphylococcal food poisoning (SFP), clinical syndromes such as skin infections, inflammation, pneumonia, and sepsis, in addition to being associated with the development of inflammation in the mammary glands of dairy cattle, which results in chronic mastitis and cell necrosis. SEs are small globular proteins that combine superantigenic and emetic activities; they are resistant to heat, low temperatures, and proteolytic enzymes and are tolerant to a wide pH range. More than 24 SE genes have been well described (SEA-SEE, SEG, SEH, SEI, SEJ, SElK, SElL, SElM, SElN, SElO, SElP, SElQ, SElR, SElS, SElT, SElU, SElV, SElW, SElX, SElY, and SElZ), being a part of different SFP outbreaks, clinical cases, and isolated animal strains. In recent years, new genes (sel26, sel27, sel28, sel31, sel32, and sel33) from SEs have been described, as well as two variants (seh-2p and ses-3p) resulting in a total of thirty-three genes from Ses, including the nine variants that are still in the process of genetic and molecular structure evaluation. SEs are encoded by genes that are located in mobile genetic elements, such as plasmids, prophages, pathogenicity islands, and the enterotoxin gene cluster (egc), and housed in the genomic island of S. aureus. Both classical SEs and SE-like toxins (SEls) share phylogenetic relationships, structure, function, and sequence homology, which are characteristics for the production of new SEs through recombination processes. Due to the epidemiological importance of SEs, their rapid assessment and detection have been crucial for food security and public health; for this reason, different methods of identification of SEs have been developed, such as liquid chromatography coupled with high-resolution mass spectrometry (LC-HRMS), molecular methods, and whole-genome sequencing; providing the diagnosis of SEs and a better understanding of the occurrence, spread, and eradication of SEs. This review provides scientific information on the enterotoxins produced by S. aureus, such as structural characteristics, genetic organization, regulatory mechanisms, superantigen activity, mechanisms of action used by SEs at the time of interaction with the immune system, methods of detection of SEs, and recent biocontrol techniques used in food.
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Affiliation(s)
- Mirian Yuliza Rubio Cieza
- Department of Food Science and Nutrition, School of Food Engineering, University of Campinas (UNICAMP), Campinas 13083-862, Brazil;
| | - Erika Carolina Romão Bonsaglia
- Department of Animal Nutrition and Production, School of Veterinary Medicine and Animal Sciences, University of São Paulo (USP), Pirassununga 13635-900, Brazil; (E.C.R.B.); (M.V.d.S.)
| | - Vera Lucia Mores Rall
- Department of Chemical and Biological Sciences, Institute of Biosciences, Sao Paulo State University, Botucatu 18618-691, Brazil;
| | - Marcos Veiga dos Santos
- Department of Animal Nutrition and Production, School of Veterinary Medicine and Animal Sciences, University of São Paulo (USP), Pirassununga 13635-900, Brazil; (E.C.R.B.); (M.V.d.S.)
| | - Nathália Cristina Cirone Silva
- Department of Food Science and Nutrition, School of Food Engineering, University of Campinas (UNICAMP), Campinas 13083-862, Brazil;
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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] [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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Cheung GYC, Otto M. Virulence Mechanisms of Staphylococcal Animal Pathogens. Int J Mol Sci 2023; 24:14587. [PMID: 37834035 PMCID: PMC10572719 DOI: 10.3390/ijms241914587] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 09/20/2023] [Accepted: 09/23/2023] [Indexed: 10/15/2023] Open
Abstract
Staphylococci are major causes of infections in mammals. Mammals are colonized by diverse staphylococcal species, often with moderate to strong host specificity, and colonization is a common source of infection. Staphylococcal infections of animals not only are of major importance for animal well-being but have considerable economic consequences, such as in the case of staphylococcal mastitis, which costs billions of dollars annually. Furthermore, pet animals can be temporary carriers of strains infectious to humans. Moreover, antimicrobial resistance is a great concern in livestock infections, as there is considerable antibiotic overuse, and resistant strains can be transferred to humans. With the number of working antibiotics continuously becoming smaller due to the concomitant spread of resistant strains, alternative approaches, such as anti-virulence, are increasingly being investigated to treat staphylococcal infections. For this, understanding the virulence mechanisms of animal staphylococcal pathogens is crucial. While many virulence factors have similar functions in humans as animals, there are increasingly frequent reports of host-specific virulence factors and mechanisms. Furthermore, we are only beginning to understand virulence mechanisms in animal-specific staphylococcal pathogens. This review gives an overview of animal infections caused by staphylococci and our knowledge about the virulence mechanisms involved.
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Affiliation(s)
| | - Michael Otto
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 50 South Drive, Bethesda, MD 20814, USA;
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Dong Q, Wang Q, Zhang Y, Chen Y, Wang H, Ding H. Prevalence, antimicrobial resistance, and staphylococcal toxin genes of bla TEM-1a -producing Staphylococcus aureus isolated from animals in Chongqing, China. Vet Med Sci 2022; 9:513-522. [PMID: 36495160 PMCID: PMC9856999 DOI: 10.1002/vms3.1028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Staphylococcus aureus infection of livestock animals and humans is a major public health issue. There are reports of antimicrobial resistance and multiple staphylococcal superantigen genes in many countries and several provinces of China, but the status in Chongqing, China is uncertain. OBJECTIVES The aim of this study was to determine the prevalence, antimicrobial susceptibility, and other molecular characteristics of S. aureus isolates from livestock animals in Chongqing. METHODS Staphylococcus aureus was isolated and identified by selective enrichment and amplification of the nuc gene from 1371 samples collected at farms in Chongqing. The agar dilution method was used to determine the resistant phenotype, and extended spectrum β-lactamase genes were amplified by PCR. Methicillin-resistant S. aureus was verified by the presence of the mecA gene, and the presence or absence of SE, SEl, and TSST-1 genes was detected in the isolates. RESULTS We cultured 89 S. aureus isolates from 1371 samples between March 2014 and December 2017. These isolates were from pigs, cattle, goats, rabbits, and chickens. There were four methicillin-resistant S. aureus strains (three from pigs and one from a chicken). The 89 isolates had high resistance to penicillin (93.3%) and ampicillin (92.1%), but most were susceptible to amikacin and ofloxacin, with resistance rates below 10%. A total of 62.9% of the isolates had varying degrees of multidrug resistance. Almost all strains, except for three isolates from chickens, were positive for blaTEM-1a . There were 19 of 20 tested staphylococcal SE/SEl/TSST-1 genes present (all except for seq), and the predominant genes were sei (58.4%), tst-1 (56.2%), and seg (51.7%). CONCLUSIONS The high antimicrobial resistance and prevalence of blaTEM-1a reinforce the need to reduce the usage of antimicrobials in livestock. The universal existence of staphylococcal toxin genes implies a potential threat to public health by animal-to-human transmission via the food chain.
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Affiliation(s)
- Qingshuang Dong
- Laboratory of Veterinary MycoplasmologyCollege of Veterinary MedicineSouthwest UniversityChongqingChina
| | - Qing Wang
- Laboratory of Veterinary MycoplasmologyCollege of Veterinary MedicineSouthwest UniversityChongqingChina
| | - Yun Zhang
- Laboratory of Veterinary MycoplasmologyCollege of Veterinary MedicineSouthwest UniversityChongqingChina
| | - Yao Chen
- Laboratory of Veterinary MycoplasmologyCollege of Veterinary MedicineSouthwest UniversityChongqingChina
| | - Haoju Wang
- Laboratory of Veterinary MycoplasmologyCollege of Veterinary MedicineSouthwest UniversityChongqingChina
| | - Honglei Ding
- Laboratory of Veterinary MycoplasmologyCollege of Veterinary MedicineSouthwest UniversityChongqingChina
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Detection of Enterotoxigenic Potential of Staphylococcus aureus Isolates from Cheese Samples with Two Different Methods. MACEDONIAN VETERINARY REVIEW 2022. [DOI: 10.2478/macvetrev-2022-0010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
The primary objective of our study was to detect the occurrence of enterotoxigenic Staphylococcus aureus in diverse types of cheese (cow's milk cheese and mixed milk cheese) samples from R.N. Macedonia. Cheese samples were analyzed for enumeration and isolation of the S. aureus strains according to ISO 6888-1. We detected the toxigenic potential of the strains by the use of the Enzyme Link Fluorescent Assay VIDAS system, and we confirmed the presence of the SEs (sea, seb, sec, sed, see) genes by multiplex PCR. The results showed that out of 270 samples of cheese, coagulase-positive staphylococci (CPS) were detected in 27 (10%), and coagulase-negative staphylococci in five samples (1.8%). Biochemically, all 27 CPS samples were confirmed to be Staphylococcus aureus. With VIDAS SET2 test we confirmed that 11 isolates are producers of one of the toxins limited by the test. With the conventional PCR we confirmed genes in only 7 isolates. Most common detected gene was seb n=3 (42.8%), followed by sea n=2 (28.6%), and sec n=2 (28.6%). Additionally, sed and see genes were not detected in any of the S. aureus isolates. Discrepancies between the two test methods for detection of enterotoxigenic potential are not uncommon. The presence of viable Staphylococcus aureus cells that have enterotoxin potency demonstrates the importance of appropriate hygiene practices in the diary process and also the maintenance of the products in order to obtain a safe final product for the consumers.
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Staphylococcal Enterotoxin Gene Cluster: Prediction of Enterotoxin (SEG and SEI) Production and of the Source of Food Poisoning on the Basis of vSaβ Typing. Appl Environ Microbiol 2021; 87:e0266220. [PMID: 33355100 PMCID: PMC8090894 DOI: 10.1128/aem.02662-20] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Besides the infection properties in human and animals, S. aureus can produce different enterotoxins in food. The enterotoxins can cause vomiting and diarrhea, often involving many people. Currently, only 5 (SEA to SEE) out of 27 known staphylococcal enterotoxins can be analyzed using commercially available kits. Six genes (seg, sei, sem, sen, seo, and seu), encoding putative and undetectable enterotoxins, are located on the enterotoxin gene cluster (egc), which is part of the Staphylococcus aureus genomic island vSaβ. These enterotoxins have been described as likely being involved in staphylococcal food-poisoning outbreaks. The aim of the present study was to determine if whole-genome data can be used for the prediction of staphylococcal egc enterotoxin production, particularly enterotoxin G (SEG) and enterotoxin I (SEI). For this purpose, whole-genome sequences of 75 Staphylococcus aureus strains from different origins (food-poisoning outbreaks, human, and animal) were investigated by applying bioinformatics methods (phylogenetic analysis using the core genome and different alignments). SEG and SEI expression was tested in vitro using a sandwich enzyme-linked immunosorbent assay method. Strains could be allocated to 14 different vSaβ types, each type being associated with a single clonal complex (CC). In addition, the vSaβ type and CC were associated with the origin of the strain (human or cattle derived). The amount of SEG and SEI produced also correlated with the vSaβ type and the CC of a strain. The present results show promising indications that the in vitro production of SEG and SEI can be predicted based on the vSaβ type or CC of a strain. IMPORTANCE Besides having infectious properties in human and animals, S. aureus can produce different enterotoxins in food. The enterotoxins can cause vomiting and diarrhea, often involving many people. Most of these outbreaks remain undiscovered, as detection methods for enterotoxins are only available for a few enterotoxins but not for the more recently discovered enterotoxins G (SEG) and I (SEI). In this study, we show promising results that in vitro production of SEG and SEI can be predicted based on the whole-genome sequencing data of a strain. In addition, these data could be used to find the source (human or cattle derived) of an outbreak strain, which is the key for a better understanding of the role SEG and SEI play in foodborne outbreaks caused by S. aureus.
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Penadés M, Viana D, García-Quirós A, Muñoz-Silvestre A, Moreno-Grua E, Pérez-Fuentes S, Pascual JJ, Corpa JM, Selva L. Differences in virulence between the two more prevalent Staphylococcus aureus clonal complexes in rabbitries (CC121 and CC96) using an experimental model of mammary gland infection. Vet Res 2020; 51:11. [PMID: 32054530 PMCID: PMC7020377 DOI: 10.1186/s13567-020-0740-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Accepted: 01/19/2020] [Indexed: 01/03/2023] Open
Abstract
Staphylococcal mastitis is a major health problem in humans and livestock that leads to economic loss running in millions. This process is currently one of the main reasons for culling adult rabbit does. Surprisingly, the two most prevalent S. aureus lineages isolated from non-differentiable natural clinical mastitis in rabbits (ST121 and ST96) generate different immune responses. This study aimed to genetically compare both types of strains to search for possible dissimilarities to explain differences in immune response, and to check whether they showed similar virulence in in vitro tests as in experimental intramammary in vivo infection. The main differences were observed in the enterotoxin gene cluster (egc) and the immune-evasion-cluster (IEC) genes. While isolate ST121 harboured all six egc cluster members (seg, sei, selm, seln, selo, selu), isolate ST96 lacked the egc cluster. Strain ST96 carried a phage integrase Sa3 (Sa3int), compatible with a phage integrated into the hlb gene (β-haemolysin-converting bacteriophages) with IEC type F, while isolate ST121 lacked IEC genes and the hlb gene was intact. Moreover, the in vitro tests confirmed a different virulence capacity between strains as ST121 showed greater cytotoxicity for erythrocytes, polymorphonuclear leukocytes and macrophages than strain ST96. Differences were also found 7 days after experimental intramammary infection with 100 colony-forming units. The animals inoculated with strain ST121 developed more severe gross and histological mastitis, higher counts of macrophages in tissue and of all the cell populations in peripheral blood, and a significantly larger total number of bacteria than those infected by strain ST96.
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Affiliation(s)
- Mariola Penadés
- Biomedical Research Institute (PASAPTA-Pathology Group), Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities. C/Tirant lo Blanc 7, Alfara del Patriarca, 46115, Valencia, Spain
| | - David Viana
- Biomedical Research Institute (PASAPTA-Pathology Group), Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities. C/Tirant lo Blanc 7, Alfara del Patriarca, 46115, Valencia, Spain
| | - Ana García-Quirós
- Biomedical Research Institute (PASAPTA-Pathology Group), Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities. C/Tirant lo Blanc 7, Alfara del Patriarca, 46115, Valencia, Spain
| | - Asunción Muñoz-Silvestre
- Biomedical Research Institute (PASAPTA-Pathology Group), Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities. C/Tirant lo Blanc 7, Alfara del Patriarca, 46115, Valencia, Spain
| | - Elena Moreno-Grua
- Biomedical Research Institute (PASAPTA-Pathology Group), Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities. C/Tirant lo Blanc 7, Alfara del Patriarca, 46115, Valencia, Spain
| | - Sara Pérez-Fuentes
- Biomedical Research Institute (PASAPTA-Pathology Group), Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities. C/Tirant lo Blanc 7, Alfara del Patriarca, 46115, Valencia, Spain
| | - Juan José Pascual
- Institute for Animal Science and Technology, Universitat Politècnica de València, Camino de Vera 14, 46071, Valencia, Spain
| | - Juan M Corpa
- Biomedical Research Institute (PASAPTA-Pathology Group), Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities. C/Tirant lo Blanc 7, Alfara del Patriarca, 46115, Valencia, Spain.
| | - Laura Selva
- Biomedical Research Institute (PASAPTA-Pathology Group), Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities. C/Tirant lo Blanc 7, Alfara del Patriarca, 46115, Valencia, Spain.
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Staphylococcus aureus enterotoxin genes detected in milk from various livestock species in northern pastoral region of Kenya. Food Control 2019. [DOI: 10.1016/j.foodcont.2019.04.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Huang TM, Chou CC. Methicillin-sensitive and methicillin-resistant Staphylococcus aureus strains and their toxin genes in the nostrils of dogs and workers at an animal shelter. J Appl Microbiol 2019; 126:1899-1909. [PMID: 30924987 DOI: 10.1111/jam.14266] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 03/16/2019] [Accepted: 03/23/2019] [Indexed: 11/30/2022]
Abstract
AIMS Methicillin-sensitive and methicillin-resistant Staphylococcus aureus (MSSA and MRSA, respectively) in the nostrils of dogs and workers at an animal shelter were cultured. Staphylococcal toxin genes were analysed to identify potential health concerns. METHODS AND RESULTS Samples were obtained from 441 dogs and 9 workers. The respective isolation rates of S. aureus and MRSA were 49·0% (216/441) and 1·6% (7/441) for shelter dogs and 44·4% (4/9) and 33·3% (3/9) for workers, respectively. Isolation of S. aureus in summer (61·9%) and in adult dogs (59·2%) were significantly higher than those in winter (35·8%) and in juvenile dogs (33·3%) (P < 0·001), respectively. The predominant enterotoxin genotypes and combination profiles of S. aureus were (sea, seb, seg, sei, sem, sen, seo, seu) and (sea, sea-seb, and seg-sei-sem-sen-seo-seu), respectively, and 20% of isolates carried food poisoning-associated enterotoxins. The se profiles in shelter dogs were different from those in general pet dogs and their owners. MRSA isolates were identified as SCCmec IV and VII, and they shared se combination profiles of (sec-seg-sei-sel-sem-sen-seo-seu) and (seb-sek-seq). MRSA in this shelter had similar microbiological characteristics as those reported in CA-MRSA ST59 in humans. CONCLUSIONS Human health-associated bacteria and food poisoning-related toxin genes were identified. Further evaluations of health concerns in animal shelters are necessary. SIGNIFICANCE AND IMPACT OF THE STUDY This is the first study to focus on se prevalence and MRSA characteristics in an animal shelter in Taiwan. The MRSA characteristics determined in this study were similar to those of CA-MRSA strains isolated from communities in the past, indicating potential health risks in cities.
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Affiliation(s)
- T-M Huang
- Department of Veterinary Medicine, National Taiwan University, Taipei, Taiwan
| | - C-C Chou
- Department of Veterinary Medicine, National Taiwan University, Taipei, Taiwan
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Haag AF, Fitzgerald JR, Penadés JR. Staphylococcus aureus in Animals. Microbiol Spectr 2019; 7:10.1128/microbiolspec.gpp3-0060-2019. [PMID: 31124433 PMCID: PMC11257167 DOI: 10.1128/microbiolspec.gpp3-0060-2019] [Citation(s) in RCA: 82] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Indexed: 12/31/2022] Open
Abstract
Staphylococcus aureus is a mammalian commensal and opportunistic pathogen that colonizes niches such as skin, nares and diverse mucosal membranes of about 20-30% of the human population. S. aureus can cause a wide spectrum of diseases in humans and both methicillin-sensitive and methicillin-resistant strains are common causes of nosocomial- and community-acquired infections. Despite the prevalence of literature characterising staphylococcal pathogenesis in humans, S. aureus is a major cause of infection and disease in a plethora of animal hosts leading to a significant impact on public health and agriculture. Infections in animals are deleterious to animal health, and animals can act as a reservoir for staphylococcal transmission to humans.Host-switching events between humans and animals and amongst animals are frequent and have been accentuated with the domestication and/or commercialisation of specific animal species. Host-switching is typically followed by subsequent adaptation through acquisition and/or loss of mobile genetic elements such as phages, pathogenicity islands and plasmids as well as further host-specific mutations allowing it to expand into new host populations.In this chapter, we will be giving an overview of S. aureus in animals, how this bacterial species was, and is, being transferred to new host species and the key elements thought to be involved in its adaptation to new ecological host niches. We will also highlight animal hosts as a reservoir for the development and transfer of antimicrobial resistance determinants.
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Affiliation(s)
- Andreas F Haag
- Institute of Infection, Immunity, and Inflammation, University of Glasgow, G12 8TA, Glasgow, UK
| | | | - José R Penadés
- Institute of Infection, Immunity, and Inflammation, University of Glasgow, G12 8TA, Glasgow, UK
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Asanin J, Misic D, Aksentijevic K, Tambur Z, Rakonjac B, Kovacevic I, Spergser J, Loncaric I. Genetic Profiling and Comparison of Human and Animal Methicillin-Resistant Staphylococcus aureus (MRSA) Isolates from Serbia. Antibiotics (Basel) 2019; 8:E26. [PMID: 30884836 PMCID: PMC6466565 DOI: 10.3390/antibiotics8010026] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Revised: 03/09/2019] [Accepted: 03/13/2019] [Indexed: 01/20/2023] Open
Abstract
The aim of this study was to characterize a collection of methicillin-resistant Staphylococcus aureus (MRSA) isolates of human and animal origin from Serbia. In total, 36 MRSA isolates-30 obtained from humans and six from companion animals-were investigated by PCR for the presence of antibiotic and biocide resistance determinants and virulence genes (PVL-Panton⁻Valentine leukocidin, ETs-exfoliative toxins, TSST-toxic shock syndrome toxin, SEs-staphylococcal enterotoxins, and MSCRAMMs-microbial surface components recognizing adhesive matrix molecules and biofilm). Isolates were analyzed by staphylococcal cassette chromosome mec (SCCmec), spa, and dru typing, as well as by multiple locus variable number of tandem repeat analyses (MLVA), multilocus sequence typing (MLST), and subsequently, eBURST. The majority of human MRSA isolates were resistant to gentamicin, erythromycin, clindamycin, and ciprofloxacin. Different antibiotic resistance genes were detected: aac-aphD, ant(6')-Ia, erm(A), erm(B), erm(C), tet(K), tet(M), fexA, and catpC221. All isolates were susceptible to teicoplanin and linezolid. SCCmec type III was prevalent in human isolates, while SCCmec elements in animals were mostly nontypeable. t037 was the predominant spa type in human and t242 in animal MRSA isolates. The prevalent dru type was dt11c in human and dt10a in animal MRSA isolates. MRSA isolates exhibited 27 different MLVA types. ST239 was predominant in human, while ST5 was prevalent in canine MRSA isolates. PVL was found in two, while tsst-1 was detected in three human isolates. Human-associated clones belonging to ST5, ST45, and ST239 MRSA clones were discovered in companion animals, which suggests anthropozoonotic transmission.
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Affiliation(s)
- Jelena Asanin
- Innovation Center of Faculty of Technology and Metallurgy, University of Belgrade, 11000 Beograd, Serbia.
| | - Dusan Misic
- Faculty of Veterinary Medicine, University of Belgrade, 11000 Beograd, Serbia.
| | | | - Zoran Tambur
- Institute of Hygiene Military Medical Academy, Belgrade, Serbia and Faculty of Stomatology in Pancevo, 11000 Beograd, Serbia.
| | - Bojan Rakonjac
- Institute of Microbiology Military Medical Academy, 11000 Beograd, Serbia.
| | - Ivana Kovacevic
- Institute of Hygiene Military Medical Academy, 11000 Beograd, Serbia.
| | - Joachim Spergser
- Institute of Microbiology, University of Veterinary Medicine, 1210 Wien, Austria.
| | - Igor Loncaric
- Institute of Microbiology, University of Veterinary Medicine, 1210 Wien, Austria.
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Dweba CC, Zishiri OT, El Zowalaty ME. Methicillin-resistant Staphylococcus aureus: livestock-associated, antimicrobial, and heavy metal resistance. Infect Drug Resist 2018; 11:2497-2509. [PMID: 30555249 PMCID: PMC6278885 DOI: 10.2147/idr.s175967] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Staphylococcus aureus is an opportunistic pathogen of human and other mammals that is of increasing clinical and veterinary importance due to its ability to rapidly develop antimicrobial resistance. The injudicious use of antibiotics has given rise to the emergence of antibiotic resistant S. aureus strains, most importantly methicillin-resistant Staphylococcus aureus (MRSA). The emergence of livestock-associated MRSA (LA-MRSA) has highlighted the importance of directed research toward its prevention, as well as the need for the discovery and development of more efficient treatment than is currently available. Furthermore, the treatment of MRSA is complicated by the co-selection of heavy metal and antibiotic resistance genes by microorganisms. Livestock and livestock production systems are large reservoirs of heavy metals due to their use in feed as well as environmental contaminant, which has allowed for the selection of LA-MRSA isolates with heavy metal resistance. The World Health Organization reported that Africa has the largest gaps in data on the prevalence of antimicrobial resistance, with no reports on rates for LA-MRSA harboring heavy metal resistance in South Africa. This review aimed to report the emergence of LA-MRSA in South Africa, specifically the most frequent sequence type ST398, globally. Furthermore, we aimed to highlight the importance of LA-MRSA in clinical and food security, as well as this research gap in South Africa. This review sheds light on the prevalence of heavy metals in livestock farms and abattoirs, and focuses on the phenomenon of the co-selection of heavy metal and antibiotic resistance genes in MRSA, emphasizing the importance of a focused direction for research in humans, animals as well as environment using one-health approach.
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Affiliation(s)
- Cwengile C Dweba
- Discipline of Genetics, School of Life Sciences, College of Agriculture Engineering and Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Oliver T Zishiri
- Discipline of Genetics, School of Life Sciences, College of Agriculture Engineering and Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Mohamed E El Zowalaty
- Microbiology and Virology Research Group, School of Health Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa,
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Wu S, Huang J, Wu Q, Zhang F, Zhang J, Lei T, Chen M, Ding Y, Xue L. Prevalence and Characterization of Staphylococcus aureus Isolated From Retail Vegetables in China. Front Microbiol 2018; 9:1263. [PMID: 29963025 PMCID: PMC6011812 DOI: 10.3389/fmicb.2018.01263] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 05/24/2018] [Indexed: 12/31/2022] Open
Abstract
Staphylococcus aureus is a pathogen associated with serious community and hospital-acquired diseases. The aim of this study was to investigate the prevalence of S. aureus from retail vegetables in China and then characterized S. aureus isolates by antibiotic resistance, staphylococcal enterotoxin genes, spa-typing and multi-locus sequence typing. Of 419 retail vegetable samples from 39 cities in China during 2011-2016, 24 (5.73%) samples were positive for S. aureus and the geometric mean was 3.85 MPN/g. The prevalence of S. aureus was highest in lettuce (13/84, 15.48%) followed by tomato (7/110, 6.36%), caraway (2/87, 2.30%), and cucumber (2/128, 1.56%), whereas other vegetables were free of S. aureus. A total of 30 isolates were analyzed. For antibiotics susceptibility test, most isolates (93.3%) were resistant to ampicillin and penicillin, whereas all isolates were susceptible to linezolid, trimethoprim/sulphamethoxazole 1:19, nitrofurantoin, rifampicin, and teicoplanin. All isolates (30/30, 100%) were resistant or intermediate resistant to more than three tested antibiotics, including 9 isolates (30%) were resisted more than 10 antibiotics. Five isolates were resistant to cefoxitin and carried mecA genes which confirmed as MRSA. Of the 18 investigated SE genes, the sem gene was the most frequently detected (86.7%) followed by the sec (83.3%), sep (70.0%), seg (56.7%), sel (53.3%), seh (50.0%), seq (50.0%), sej (46.7%), seb (36.7%), sen (36.7%), and ser (33.3%) genes were harbored by more than one third of the isolates, whereas the seo and seu were detected in only 6.75% of the isolates. MLST and spa typing observed high genetic diversity in S. aureus isolated from retail vegetable in China. ST59-t437 was the predominant types (3/5, 60%) of MRSA isolates, whereas ST188-t189 was the predominant types (7/25, 28%) of MSSA isolates. Our study reflects that the retail vegetable in China could be contaminated with S. aureus but the levels of S. aureus were not very excessive. In addition, these isolates had virulence potential, most of them were enterotoxigenic and multiple antimicrobial resistance, should be draw public attention. These data have signification implications for epidemiological and public health studies of this pathogen.
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Affiliation(s)
- Shi Wu
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangzhou, China
| | - Jiahui Huang
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangzhou, China
| | - Qingping Wu
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangzhou, China
| | - Feng Zhang
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangzhou, China
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangzhou, China
| | - Jumei Zhang
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangzhou, China
| | - Tao Lei
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangzhou, China
| | - Moutong Chen
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangzhou, China
| | - Yu Ding
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangzhou, China
| | - Liang Xue
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangzhou, China
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Tuffs SW, Haeryfar SMM, McCormick JK. Manipulation of Innate and Adaptive Immunity by Staphylococcal Superantigens. Pathogens 2018; 7:pathogens7020053. [PMID: 29843476 PMCID: PMC6027230 DOI: 10.3390/pathogens7020053] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 05/15/2018] [Accepted: 05/17/2018] [Indexed: 12/15/2022] Open
Abstract
Staphylococcal superantigens (SAgs) constitute a family of potent exotoxins secreted by Staphylococcus aureus and other select staphylococcal species. SAgs function to cross-link major histocompatibility complex (MHC) class II molecules with T cell receptors (TCRs) to stimulate the uncontrolled activation of T lymphocytes, potentially leading to severe human illnesses such as toxic shock syndrome. The ubiquity of SAgs in clinical S. aureus isolates suggests that they likely make an important contribution to the evolutionary fitness of S. aureus. Although the apparent redundancy of SAgs in S. aureus has not been explained, the high level of sequence diversity within this toxin family may allow for SAgs to recognize an assorted range of TCR and MHC class II molecules, as well as aid in the avoidance of humoral immunity. Herein, we outline the major diseases associated with the staphylococcal SAgs and how a dysregulated immune system may contribute to pathology. We then highlight recent research that considers the importance of SAgs in the pathogenesis of S. aureus infections, demonstrating that SAgs are more than simply an immunological diversion. We suggest that SAgs can act as targeted modulators that drive the immune response away from an effective response, and thus aid in S. aureus persistence.
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Affiliation(s)
- Stephen W Tuffs
- Department of Microbiology and Immunology, Schulich School of Medicine and Dentistry, Western University, London, ON N6A 5C1, Canada.
| | - S M Mansour Haeryfar
- Department of Microbiology and Immunology, Schulich School of Medicine and Dentistry, Western University, London, ON N6A 5C1, Canada.
- Division of Clinical Immunology and Allergy, Department of Medicine, Western University, London, ON N6A 3K7, Canada.
- Centre for Human Immunology, Western University, London, ON N6A 3K7, Canada.
- Lawson Health Research Institute, London, ON N6C 2R5, Canada.
| | - John K McCormick
- Department of Microbiology and Immunology, Schulich School of Medicine and Dentistry, Western University, London, ON N6A 5C1, Canada.
- Centre for Human Immunology, Western University, London, ON N6A 3K7, Canada.
- Lawson Health Research Institute, London, ON N6C 2R5, Canada.
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15
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Artursson K, Schelin J, Thisted Lambertz S, Hansson I, Olsson Engvall E. Foodborne pathogens in unpasteurized milk in Sweden. Int J Food Microbiol 2018; 284:120-127. [PMID: 29887505 DOI: 10.1016/j.ijfoodmicro.2018.05.015] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 05/11/2018] [Accepted: 05/17/2018] [Indexed: 11/15/2022]
Abstract
Raw milk may be a risk for public health if it is contaminated with zoonotic pathogens. To study the prevalence in unpasteurized milk from Swedish farms, bovine and small ruminant dairy farms were sampled. Since the sampling method and transport conditions may influence the outcome of analyses, efforts were made to optimize the methodology. Culturing of bacteria was done from in-line milk filters collected from the milk pipe at the point where it enters the milk bulk tank at the farms and this way of sampling was compared to sampling bulk tank milk (BTM) directly. Analysing milk filters were found to be superior to analysing BTM directly. Conditions for transport of milk filter samples were further improved by the addition of Cary Blair transport medium, which significantly increased the number of positive samples for pathogenic bacteria. The isolation of several foodborne pathogens from milk filters was demonstrated. The prevalence of samples with Staphylococcus aureus was 71% and 64%, and Listeria spp. 21% and 29% from dairy cow and goat/sheep farms, respectively. Campylobacter jejuni, Yersinia enterocolitica and verotoxigenic Escherichia coli (VTEC) O157 were detected in 9%, 2% and 2% of samples from bovine milk, respectively. We conclude that the choice of sampling method and sample handling influence the results of bacterial culturing. From the results of this study, we strongly recommend to sample in-line milk filters instead of BTM directly and to use Cary Blair medium during transport, especially if the samples are to be analysed for Campylobacter spp. and/or Listeria spp. The findings also show that unpasteurized milk from Swedish farms occasionally contain bacteria with zoonotic potential.
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Affiliation(s)
- Karin Artursson
- National Veterinary Institute, Uppsala, Sweden; Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Sweden.
| | - Jenny Schelin
- Applied Microbiology, Faculty of Engineering, Lund University, Lund, Sweden
| | - Susanne Thisted Lambertz
- Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Sweden; National Food Agency, Uppsala, Sweden
| | - Ingrid Hansson
- National Veterinary Institute, Uppsala, Sweden; Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Sweden
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Vitale M, Gaglio S, Galluzzo P, Cascone G, Piraino C, Di Marco Lo Presti V, Alduina R. Antibiotic Resistance Profiling, Analysis of Virulence Aspects and Molecular Genotyping of Staphylococcus aureus Isolated in Sicily, Italy. Foodborne Pathog Dis 2017; 15:177-185. [PMID: 29260903 PMCID: PMC5865246 DOI: 10.1089/fpd.2017.2338] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Staphylococcus aureus is the major cause of foodborne diseases worldwide. In this retrospective study, 84 S. aureus strains were characterized. The collection comprises 78 strains isolated during 1998 and 2014 from dairy products and tissue samples from livestock bred for dairy production in Sicily. One isolate was obtained from a pet (dog), one from an exotic animal (a circus elephant), and four human isolates were obtained during a severe food poisoning outbreak that occurred in Sicily in 2015. All the strains were characterized by pulsed-field gel electrophoresis (PFGE), for antibiotic resistance and presence of toxin genes. PFGE results showed 10 different pulsotypes, with three relatively frequent and three unique. The antibiotic resistance profiling showed that penicillin G (35.7%) and tetracycline (20.2%) resistance is largely spread. Most isolates contained at least one toxin gene making them a potential threat for public health. Enterotoxin sec gene was observed in 28.6% and seg in 23.8% of the strains, respectively; the human isolates were the only ones to concurrently harbor both seg and sei genes. In addition, 24 isolates were randomly selected and analyzed by multilocus sequence typing. Interestingly, the analysis showed the presence of 12 sequence types (STs), of which 6 were novel. One of them, ST700, was detected in 29% of the isolates and was found to be spread throughout Sicily. ST700 has been present in the island for almost 16 years (1998–2014) and it shows no host preference since it was isolated from different ruminant species. Four human isolates shared both the pulsotype (PT10) and the sequence type (ST9), as well as the virulence genes (seg-sei); this observation suggests that the isolates originated from a single clone, although they were obtained from two different individuals.
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Affiliation(s)
- Maria Vitale
- 1 Istituto Zooprofilattico Sperimentale della Sicilia , Palermo, Italy
| | - Salvatore Gaglio
- 1 Istituto Zooprofilattico Sperimentale della Sicilia , Palermo, Italy
| | - Paola Galluzzo
- 1 Istituto Zooprofilattico Sperimentale della Sicilia , Palermo, Italy
| | - Giuseppe Cascone
- 1 Istituto Zooprofilattico Sperimentale della Sicilia , Palermo, Italy
| | - Chiara Piraino
- 1 Istituto Zooprofilattico Sperimentale della Sicilia , Palermo, Italy
| | | | - Rosa Alduina
- 2 Dipartimento Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche, Viale delle Scienze, University of Palermo , Palermo, Italy
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Schmidt T, Kock MM, Ehlers MM. Molecular Characterization of Staphylococcus aureus Isolated from Bovine Mastitis and Close Human Contacts in South African Dairy Herds: Genetic Diversity and Inter-Species Host Transmission. Front Microbiol 2017; 8:511. [PMID: 28428772 PMCID: PMC5382207 DOI: 10.3389/fmicb.2017.00511] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 03/13/2017] [Indexed: 11/20/2022] Open
Abstract
Staphylococcus aureus is one of the most common etiological agents of contagious bovine mastitis worldwide. The purpose of this study was to genetically characterize a collection of S. aureus isolates (bovine = 146, human = 12) recovered from cases of bovine mastitis and nasal swabs of close human contacts in the dairy environment. Isolates were screened for a combination of clinically significant antimicrobial and virulence gene markers whilst the molecular epidemiology of these isolates and possible inter-species host transmission was investigated using a combination of genotyping techniques. None of the isolates under evaluation tested positive for methicillin or vancomycin resistance encoding genes. Twenty seven percent of the bovine S. aureus isolates tested positive for one or more of the pyrogenic toxin superantigen (PTSAg) genes with the sec and sell genes predominating. Comparatively, 83% of the human S. aureus isolates tested positive for one or more PTSAg genes with a greater variety of genes being detected. Genomic DNA macrorestriction followed by pulsed-field gel electrophoresis (PFGE) of the bovine isolates generated 58 electrophoretic patterns which grouped into 10 pulsotypes at an 80% similarity level. The majority of the bovine isolates, 93.2% (136/146), clustered into four major pulsotypes. Seven sequence types (ST) were identified among the representative bovine S. aureus isolates genotyped, including: ST8 (CC8), ST97 (CC97), ST351 (CC705), ST352 (CC97), ST508 (CC45), ST2992 (CC97) and a novel sequence type, ST3538 (CC97). Based on PFGE analysis, greater genetic diversity was observed among the human S. aureus isolates. Bovine and human isolates from three sampling sites clustered together and were genotypically indistinguishable. Two of the isolates, ST97 and ST352 belong to the common bovine lineage CC97, and their isolation from close human contacts suggests zoonotic transfer. In the context of this study, the third isolate, ST8 (CC8), is believed to be a human clone which has transferred to a dairy cow and has subsequently caused mastitis. The detection of indistinguishable S. aureus isolates from bovine and human hosts at three of the sampling sites is suggestive of bacterial transmission and supports the need for vigilant monitoring of staphylococcal populations at the human-animal interface.
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Affiliation(s)
- Tracy Schmidt
- Allerton Provincial Veterinary Laboratory, KwaZulu-Natal Department of Agriculture and Rural DevelopmentPietermaritzburg, South Africa.,Department of Medical Microbiology, University of PretoriaPretoria, South Africa
| | - Marleen M Kock
- Department of Medical Microbiology, University of PretoriaPretoria, South Africa.,Tshwane Academic Division, National Health Laboratory ServicePretoria, South Africa
| | - Marthie M Ehlers
- Department of Medical Microbiology, University of PretoriaPretoria, South Africa.,Tshwane Academic Division, National Health Laboratory ServicePretoria, South Africa
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18
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Becker K, Ballhausen B, Kahl BC, Köck R. The clinical impact of livestock-associated methicillin-resistant Staphylococcus aureus of the clonal complex 398 for humans. Vet Microbiol 2017; 200:33-38. [DOI: 10.1016/j.vetmic.2015.11.013] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 11/12/2015] [Indexed: 11/30/2022]
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19
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Isolation of Methicillin-Resistant Staphylococcus aureus Strains Producing Enterotoxins A, K and Q From Chicken Meat in Isfahan, Iran, 2014. ARCHIVES OF CLINICAL INFECTIOUS DISEASES 2016. [DOI: 10.5812/archcid.35601] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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20
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McMillan K, Moore SC, McAuley CM, Fegan N, Fox EM. Characterization of Staphylococcus aureus isolates from raw milk sources in Victoria, Australia. BMC Microbiol 2016; 16:169. [PMID: 27473328 PMCID: PMC4966798 DOI: 10.1186/s12866-016-0789-1] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 07/27/2016] [Indexed: 12/23/2022] Open
Abstract
Background Highly pathogenic strains of Staphylococcus aureus can cause disease in both humans and animals. In animal species, including ruminants, S. aureus may cause severe or sub-clinical mastitis. Dairy animals with mastitis frequently shed S. aureus into the milk supply which can lead to food poisoning in humans. The aim of this study was to use genotypic and immunological methods to characterize S. aureus isolates from milk-related samples collected from 7 dairy farms across Victoria. Results A total of 30 S. aureus isolates were collected from milk and milk filter samples from 3 bovine, 3 caprine and 1 ovine dairy farms across Victoria, Australia. Pulsed Field Gel Electrophoresis (PFGE) identified 11 distinct pulsotypes among isolates; all caprine and ovine isolates shared greater than 80 % similarity regardless of source. Conversely, bovine isolates showed higher diversity. Multi-Locus Sequence Typing (MLST) identified 5 different sequence types (STs) among bovine isolates, associated with human or ruminant lineages. All caprine and ovine isolates were ST133, or a single allele variant of ST133. Two new novel STs were identified among isolates in this study (ST3183 and ST3184). With the exception of these 2 new STs, eBURST analysis predicted all other STs to be founding members of their associated clonal complexes (CCs). Analysis of genetic markers revealed a diverse range of classical staphylococcal enterotoxins (SE) among isolates, with 11 different SEs identified among bovine isolates, compared with just 2 among caprine and ovine isolates. None of the isolates contained mecA, or were resistant to oxacillin. The only antibiotic resistance identified was that of a single isolate resistant to penicillin; this isolate also contained the penicillin resistance gene blaZ. Production of SE was observed at 16 °C and/or 37 °C in milk, however no SE production was detected at 12 °C. Conclusion Although this study characterized a limited number of isolates, bovine-associated isolates showed higher genetic diversity than their caprine or ovine counterparts. This was also reflected in a more diverse SE repertoire among bovine isolates. Very little antibiotic resistance was identified among isolates in this study. These results suggest maintaining the milk cold chain will minimise any risk from SE production and highlights the need to prevent temperature abuse.
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Affiliation(s)
- Kate McMillan
- CSIRO Agriculture and Food, PO Box 745, Archerfield BC, QLD 4108, Australia
| | - Sean C Moore
- CSIRO Agriculture and Food, 671 Sneydes Road, Werribee, VIC 3030, Australia
| | | | - Narelle Fegan
- CSIRO Agriculture and Food, 671 Sneydes Road, Werribee, VIC 3030, Australia
| | - Edward M Fox
- CSIRO Agriculture and Food, 671 Sneydes Road, Werribee, VIC 3030, Australia.
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Gharsa H, Ben Slama K, Gómez-Sanz E, Lozano C, Zarazaga M, Messadi L, Boudabous A, Torres C. Molecular characterization of Staphylococcus aureus from nasal samples of healthy farm animals and pets in Tunisia. Vector Borne Zoonotic Dis 2016; 15:109-15. [PMID: 25700041 DOI: 10.1089/vbz.2014.1655] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
A total of 261 healthy farm and pet animals (75 cattle, 52 goats, 100 dogs, and 34 cats) from different regions of Tunisia were screened for Staphylococcus aureus nasal carriage. Molecular typing of isolates (by spa- and multilocus sequence-typing) was performed, and their antimicrobial resistance and virulence genotypes were determined by PCR and sequencing. S. aureus isolates were detected in 17 of 261 tested samples (6.5%). All S. aureus isolates recovered were methicillin-susceptible (MSSA), and one isolate/sample was further studied. Eight different spa types were detected (t189, t279, t582, t701, t1166, t1268, t1534, and t1773), and eight different sequence types were identified (ST6, ST15, ST45, ST133, ST188, ST700 [clonal complex CC130], ST2057, and a new ST2121). MSSA from pets (six isolates) showed resistance to (number of isolates, resistance gene): penicillin (six, blaZ), tetracycline (one, tet[M]), erythromycin one, erm[A]), streptomycin (one, ant[6]-Ia), and ciprofloxacin (one). All isolates from farm animals showed susceptibility to the tested antimicrobials, except for two penicillin-resistant isolates. Five S. aureus isolates from goats and cats harbored the lukF/lukS-PV genes, encoding the Panton-Valentine leukocidin, and six isolates from goats harbored the tst virulence gene. In addition, diverse combinations of enterotoxin genes were detected, including two variants of the egc cluster. Goats and cats could represent a reservoir of important toxin genes, with potential implications in animal and human health.
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Affiliation(s)
- Haythem Gharsa
- 1 Laboratoire des Microorganismes et Biomolécules Actives, Faculté des Sciences de Tunis, Université Tunis-El Manar , Tunis, Tunisia
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Gogoi-Tiwari J, Waryah CB, Eto KY, Tau M, Wells K, Costantino P, Tiwari HK, Isloor S, Hegde N, Mukkur T. Relative distribution of virulence-associated factors among Australian bovine Staphylococcus aureus isolates: Potential relevance to development of an effective bovine mastitis vaccine. Virulence 2016; 6:419-23. [PMID: 26103596 DOI: 10.1080/21505594.2015.1043508] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Affiliation(s)
- Jully Gogoi-Tiwari
- a School of Biomedical Sciences; Faculty of Health Sciences; Curtin Health Innovation Research Institute; CHIRI Biosciences Research Precinct; Curtin University ; Perth , Australia
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23
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Virulence gene profiles in Staphylococcus aureus isolated from cows with subclinical mastitis in eastern Poland. J DAIRY RES 2016; 83:228-35. [PMID: 27032339 DOI: 10.1017/s002202991600008x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Staphylococcus aureus is arguably the most important pathogen involved in bovine mastitis. The aim of this study was to determine the virulence gene profiles of 124 Staph. aureus isolates from subclinical mastitis in cows in eastern Poland. The presence of 30 virulence genes encoding adhesins, proteases and superantigenic toxins was investigated by PCR. The 17 different combinations of adhesin genes were identified. Occurrence of eno (91·1%) and fib (82·3%) genes was found to be common. The frequency of other adhesion genes fnbA, fnbB, ebps were 14·5, 50, 25%, respectively, and for cna and bbp were 1·6%. The etA and etD genes, encoding exfoliative toxins, were present in genomes of 5·6 and 8·9% isolates, respectively. The splA and sspA, encoding serine protease, were detected in above 90% isolates. The most frequent enterotoxin genes were sei (21%), sem (19·4%), sen (19·4%), seg (18·5%) and seo (13·7%). The tst gene was harboured by 2·4% isolates. The 19 combinations of the superantigenic toxin genes were obtained and found in 35·5% of isolates. Three of them (seg, sei, sem, sen, seo; sec, seg, sei, sem, sen, seo and seg, sei, sem, sen) were the most frequent and found in 16·1% of the isolates. The most common virulotype, present in 17·7% of the isolates, was fib, eno, fnbB, splA, splE, sspA. The results indicate the variation in the presence of virulence genes in Staph. aureus isolates and considerable diversity of isolates that are able to cause mastitis in cows.
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Merz A, Stephan R, Johler S. Staphylococcus aureus Isolates from Goat and Sheep Milk Seem to Be Closely Related and Differ from Isolates Detected from Bovine Milk. Front Microbiol 2016; 7:319. [PMID: 27014240 PMCID: PMC4789554 DOI: 10.3389/fmicb.2016.00319] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 02/29/2016] [Indexed: 11/13/2022] Open
Abstract
Dairy goat and sheep farms suffer severe economic losses due to intramammary infections, with Staphylococcus aureus representing the main cause of clinical mastitis in small ruminants. In addition, S. aureus contamination of goat and sheep milk may cause staphylococcal food poisoning, as many traditional caprine and ovine milk products are not subjected to pasteurization. Data on virulence and antimicrobial resistance genes, as well as on the clonality of S. aureus detected in goat and sheep milk is scarce. Therefore, it was the aim of this study to determine (i) spa types and clonal complexes (CC) and (ii) virulence and resistance gene profiles of S. aureus isolated from goat and sheep milk. A total of 162 milk samples from sheep and goats presenting signs of an intramammary infection and 104 bulk milk samples were collected. While low prevalence rates of S. aureus was detected on single animal level, 46% of the bulk tank milk samples from small ruminants were positive for S. aureus. All isolates were spa typed and CC and virulence and resistance gene patterns were determined using a DNA microarray. Data from 49 S. aureus isolates was included in the statistical analysis and the construction of a SplitsTree. The analyzed isolates could be assigned to eleven CC, with the large majority of goat and sheep isolates being assigned to CC130 and CC133. The findings of this study suggest that S. aureus shows pronounced adaptation to small ruminants in general, but not to sheep or goats in particular. Although some common characteristics among S. aureus from caprine, ovine, and bovine milk samples were observed, S. aureus from small ruminants seem to form a distinct population. As 67% of the detected S. aureus strains exhibited at least one enterotoxin gene, many caprine, or ovine raw milk products may be contaminated with low levels of enterotoxigenic S. aureus, stressing the importance of strict maintenance of the cold chain.
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Affiliation(s)
- Axel Merz
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich Zurich, Switzerland
| | - Roger Stephan
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich Zurich, Switzerland
| | - Sophia Johler
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich Zurich, Switzerland
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Characteristics of Virulence Factors in Methicillin-Resistant Staphylococcus aureus Strains Isolated From a Referral Hospital in Tehran, Iran. ARCHIVES OF CLINICAL INFECTIOUS DISEASES 2016. [DOI: 10.5812/archcid.33220] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Genotyping and DNA microarray based characterization of Staphylococcus aureus isolates from rabbit carcasses. Meat Sci 2015; 112:86-9. [PMID: 26555564 DOI: 10.1016/j.meatsci.2015.11.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 10/03/2015] [Accepted: 11/02/2015] [Indexed: 11/20/2022]
Abstract
Staphylococcus aureus can cause staphylococcal food poisoning. Although the organism is frequently detected on rabbit carcasses, little is known about the characteristics of S. aureus strains contaminating rabbit meat. In this study, 137 S. aureus isolates originating from 137 rabbit carcasses were spa typed and characterized by DNA microarray. The isolates were assigned to CC5, CC7, CC8, CC15, CC96, CC101, CC121, and ST890, and to 13 spa types (t056, t085, t091, t160, t179, t681, t741, t745, t1190, t1773, t4770, t8456, t14871). Enterotoxin genes detected included sea, sed, sej, and ser. In addition, the egc operon, encoding the newly described staphylococcal enterotoxins SEG/SEI/SElM/SElN/SElO/SElU, was found in all isolates except those of t091. While none of the examined isolates presented genes conferring methicillin, vancomycin, or aminoglycoside resistance, we frequently detected blaZ/I/R conferring resistance to penicillin. The isolates represented a heterogeneous group assigned to clonal lineages detected among humans and animals, with two spa types exclusively associated with rabbit meat (t4770, t8456).
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Viana Martín D, Selva L, Penadés M, Corpa JM. Screening of virulence genes in Staphylococcus aureus isolates from rabbits. WORLD RABBIT SCIENCE 2015. [DOI: 10.4995/wrs.2015.3961] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
<p><em>Staphylococcus aureus</em> is a versatile pathogen able to cause disease in both humans and animals. In rabbits, this bacterium infects animals of different ages, producing several purulent lesions. The ability of <em>S. aureus</em> to cause disease depends on a combination of virulence factors. The aim of this study was therefore to investigate the distribution of bacterial virulence determinants in 69 <em>S. aureus</em> isolates from rabbits. Some virulence factors (7 adhesins, 1 toxin and 1 protease) were positive in all rabbit <em>S. aureus</em> isolates analysed, while others (1 adhesin and 10 toxins) were always negative. The remaining virulence factors were more variable among isolates. An association between genotype and the different profiles of virulence factors was observed, but not with the type of lesion (P<0.05). One strain of each genotype was further analysed by multilocus sequence typing, generating ST121, ST96 and ST2951, determining a greater number of enterotoxins in ST121 isolates compared to ST96 and ST2951 isolates, which could justify the different pathogenicity between strains. </p>
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Alibayov B, Zdenkova K, Sykorova H, Demnerova K. Molecular analysis of Staphylococcus aureus pathogenicity islands (SaPI) and their superantigens combination of food samples. J Microbiol Methods 2015; 107:197-204. [PMID: 25447888 DOI: 10.1016/j.mimet.2014.10.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2014] [Revised: 10/24/2014] [Accepted: 10/25/2014] [Indexed: 10/24/2022]
Abstract
Staphylococcus aureus produces a wide variety of superantigenic activity Staphylococcal enterotoxins (SE) and they are a major cause of food poisoning. These superantigens are associated with mobile genetic elements such as plasmids, prophages and S. aureus pathogenicity islands (SaPI). The presence of well-known eight SaPI integrase and 13 enterotoxin genes (sea, seb, sec, sed, see, seg, seh, sei, sej, sel, sek, seq, and tst) in 93 S. aureus strains were investigated. All S. aureus isolates were characterized by pulsed-field gel electrophoresis (PFGE), and the genes were detected using five sets of multiplex PCR (mPCR). The most predominant toxin genes were sea (19%), seb (15%), sec (54%), sell (48%), selk (46%), selq (52%), seg (22%), and sei (19%). Analysis showed that many S. aureus isolates harbored multiple toxin genes. An mPCR-based assay was developed for the determination of all SaPI and their superantigen gene combinations. Twenty three isolates revealed the gene combination sec, sell and tst, typical of the SaPIbov1 and SaPIn1/m1 pathogenicity islands. Twelve isolates revealed the selk and selq gene combination consistent with SaPI3. Eight isolates exhibited the sec and sell genes without the tst gene typical of SaPImw2. We established a correlation between superantigenic toxin genotypes in S. aureus in terms of combinations of toxin gene-encoding SaPI. These results provide a rapid method for determining superantigenic toxin genotypes in S. aureus strains. A total of 24 PFGE patterns were generated. To our knowledge, this is a first study analyzing the correlation of all known SaPI and their enterotoxins in S. aureus using mPCR.
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Affiliation(s)
- Babek Alibayov
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, Institute of Chemical Technology, Prague, Czech Republic.
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Koymans KJ, Vrieling M, Gorham RD, van Strijp JAG. Staphylococcal Immune Evasion Proteins: Structure, Function, and Host Adaptation. Curr Top Microbiol Immunol 2015; 409:441-489. [PMID: 26919864 DOI: 10.1007/82_2015_5017] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Staphylococcus aureus is a successful human and animal pathogen. Its pathogenicity is linked to its ability to secrete a large amount of virulence factors. These secreted proteins interfere with many critical components of the immune system, both innate and adaptive, and hamper proper immune functioning. In recent years, numerous studies have been conducted in order to understand the molecular mechanism underlying the interaction of evasion molecules with the host immune system. Structural studies have fundamentally contributed to our understanding of the mechanisms of action of the individual factors. Furthermore, such studies revealed one of the most striking characteristics of the secreted immune evasion molecules: their conserved structure. Despite high-sequence variability, most immune evasion molecules belong to a small number of structural categories. Another remarkable characteristic is that S. aureus carries most of these virulence factors on mobile genetic elements (MGE) or ex-MGE in its accessory genome. Coevolution of pathogen and host has resulted in immune evasion molecules with a highly host-specific function and prevalence. In this review, we explore how these shared structures and genomic locations relate to function and host specificity. This is discussed in the context of therapeutic options for these immune evasion molecules in infectious as well as in inflammatory diseases.
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Affiliation(s)
- Kirsten J Koymans
- Department of Medical Microbiology, University Medical Center Utrecht, G04-614, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.
| | - Manouk Vrieling
- Department of Medical Microbiology, University Medical Center Utrecht, G04-614, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
| | - Ronald D Gorham
- Department of Medical Microbiology, University Medical Center Utrecht, G04-614, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
| | - Jos A G van Strijp
- Department of Medical Microbiology, University Medical Center Utrecht, G04-614, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
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Staphylococcus aureus in veterinary medicine. INFECTION GENETICS AND EVOLUTION 2013; 21:602-15. [PMID: 23974078 DOI: 10.1016/j.meegid.2013.08.011] [Citation(s) in RCA: 149] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Revised: 08/12/2013] [Accepted: 08/15/2013] [Indexed: 11/24/2022]
Abstract
Staphylococcus aureus is a major opportunistic pathogen in humans and one of the most important pathogenic Staphylococcus species in veterinary medicine. S. aureus is dangerous because of its deleterious effects on animal health and its potential for transmission from animals to humans and vice-versa. It thus has a huge impact on animal health and welfare and causes major economic losses in livestock production. Increasing attention is therefore being paid to both livestock and companion animals in terms of this pathogen. In this review, we summarise the current knowledge on the animal host adaptation of S. aureus. Different types of S. aureus infections in animals are also presented, with particular emphasis on mastitis in dairy herds, which is probably the costliest and therefore the best documented S. aureus infection seen in animals.
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Ebner R, Johler S, Sihto HM, Stephan R, Zweifel C. Microarray-based characterization of Staphylococcus aureus isolates obtained from chicken carcasses. J Food Prot 2013; 76:1471-4. [PMID: 23905809 DOI: 10.4315/0362-028x.jfp-13-009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A total of 34 Staphylococcus aureus isolates from flock-wise pooled chicken neck skin samples collected at two abattoirs during slaughter were characterized with DNA microarray analysis and spa typing. The 20 isolates from abattoir A all belonged to clonal complex (CC) 12 and spa type t160. Of the 14 isolates from abattoir B, 7 belonged to CC5-t3478, 5 to CC12-t160, 1 to CC45-t040, and 1 to CC101-t056. Of the various resistance-associated genes tested, only blaZ/R/I (6 isolates of CC12 and CC101 from abattoir B), sdrM (n = 34), fosB (n = 33), and qacC (n = 22) were detected. None of the isolates harbored genes conferring methicillin resistance. In terms of genes encoding enterotoxins, seb (all isolates of CC12), egc (seg, sei, selm, seln, selo, selu; all isolates of CC5 and CC45), and sea (14 isolates of CC12 and 1 isolate of CC5) were found. In addition, all isolates harbored genes for intracellular adhesion proteins (icaA/C/D) and were positive for cap5 or cap8 (capsule type 5 or 8). Comparison of DNA microarray profiles identified four categories comprising (i) all isolates of CC12, (ii) all isolates of CC5, (iii) the CC45 isolate, and (iv) the CC101 isolate. The high similarity of the isolates from abattoir A could indicate contamination of chicken carcasses with S. aureus persisting on the slaughter equipment, but further investigations are required to elucidate potential contamination routes.
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Affiliation(s)
- Rebecca Ebner
- Institute for Food Safety and Hygiene, Vetsuisse Faculty University of Zurich, Winterthurerstrasse 272, 8057 Zurich, Switzerland
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Viçosa GN, Le Loir A, Le Loir Y, de Carvalho AF, Nero LA. egc characterization of enterotoxigenic Staphylococcus aureus isolates obtained from raw milk and cheese. Int J Food Microbiol 2013; 165:227-30. [PMID: 23800734 DOI: 10.1016/j.ijfoodmicro.2013.05.023] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Revised: 05/27/2013] [Accepted: 05/28/2013] [Indexed: 11/19/2022]
Abstract
Genes encoding staphylococcal enterotoxins (SEs) are carried by mobile genetic elements, and enterotoxin gene clusters (egc) are pathogenicity island-borne structures comprising several SE genes, which are frequently found among clinical Staphylococcus aureus isolates. In the present study, we investigated the distribution and the genetic variability of egc loci in S. aureus strains isolated from raw milk and soft cheese in Minas Gerais, Brazil. Ninety-two isolates were submitted to PCR detection of individual egc-borne SE genes (seg, sei, sem, sen, seo, seu), and egc loci were typed using PCR-RFLP. PCR products of egc positive isolates were sequenced. Ninety-one isolates harbored at least one SE gene, which generated 14 different genotypes. The sei gene was the most widely distributed (97.8%), and was found in combination with seg in 49 isolates (53.3%). Altogether, a complete set of individual egc genes was detected in 37 isolates (40%). However, egc loci were detected by PCR-RFLP in only 4 isolates, and classified as egc1 (n=2), egc3 (n=1), and egc4 (n=1). This investigation demonstrated the low occurrence of the egc in S. aureus isolated from dairy products. However, the frequency of complete sets of individual egc-borne genes reflects either the presence of these SE genes outside egc or the existence of new egc types in these strains.
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Human-to-bovine jump of Staphylococcus aureus CC8 is associated with the loss of a β-hemolysin converting prophage and the acquisition of a new staphylococcal cassette chromosome. PLoS One 2013; 8:e58187. [PMID: 23505465 PMCID: PMC3594393 DOI: 10.1371/journal.pone.0058187] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Accepted: 01/31/2013] [Indexed: 12/31/2022] Open
Abstract
Staphylococcus aureus can colonize and infect both humans and animals, but isolates from both hosts tend to belong to different lineages. Our recent finding of bovine-adapted S. aureus showing close genetic relationship to the human S. aureus clonal complex 8 (CC8) allowed us to examine the genetic basis of host adaptation in this particular CC. Using total chromosome microarrays, we compared the genetic makeup of 14 CC8 isolates obtained from cows suffering subclinical mastitis, with nine CC8 isolates from colonized or infected human patients, and nine S. aureus isolates belonging to typical bovine CCs. CC8 isolates were found to segregate in a unique group, different from the typical bovine CCs. Within this CC8 group, human and bovine isolates further segregated into three subgroups, among which two contained a mix of human and bovine isolates, and one contained only bovine isolates. This distribution into specific clusters and subclusters reflected major differences in the S. aureus content of mobile genetic elements (MGEs). Indeed, while the mixed human-bovine clusters carried commonly human-associated β-hemolysin converting prophages, the bovine-only isolates were devoid of such prophages but harbored an additional new non-mec staphylococcal cassette chromosome (SCC) unique to bovine CC8 isolates. This composite cassette carried a gene coding for a new LPXTG-surface protein sharing homologies with a protein found in the environmental bacterium Geobacillus thermoglucosidans. Thus, in contrast to human CC8 isolates, the bovine-only CC8 group was associated with the combined loss of β-hemolysin converting prophages and gain of a new SCC probably acquired in the animal environment. Remaining questions are whether the new LPXTG-protein plays a role in bovine colonization or infection, and whether the new SCC could further acquire antibiotic-resistance genes and carry them back to human.
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Wan MT, Lauderdale TL, Chou CC. Characteristics and virulence factors of livestock associated ST9 methicillin-resistant Staphylococcus aureus with a novel recombinant staphylocoagulase type. Vet Microbiol 2013; 162:779-784. [DOI: 10.1016/j.vetmic.2012.10.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Revised: 09/30/2012] [Accepted: 10/03/2012] [Indexed: 10/27/2022]
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Molecular characterization of enterotoxigenic and borderline oxacillin resistant Staphylococcus strains from ovine milk. Food Microbiol 2012; 32:265-73. [DOI: 10.1016/j.fm.2012.06.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Revised: 06/11/2012] [Accepted: 06/28/2012] [Indexed: 11/22/2022]
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Gharsa H, Ben Sallem R, Ben Slama K, Gómez-Sanz E, Lozano C, Jouini A, Klibi N, Zarazaga M, Boudabous A, Torres C. High diversity of genetic lineages and virulence genes in nasal Staphylococcus aureus isolates from donkeys destined to food consumption in Tunisia with predominance of the ruminant associated CC133 lineage. BMC Vet Res 2012; 8:203. [PMID: 23107174 PMCID: PMC3538696 DOI: 10.1186/1746-6148-8-203] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Accepted: 10/22/2012] [Indexed: 12/14/2022] Open
Abstract
Background The objective of this study was to determine the genetic lineages and the incidence of antibiotic resistance and virulence determinants of nasal Staphylococcus aureus isolates of healthy donkeys destined to food consumption in Tunisia. Results Nasal swabs of 100 donkeys obtained in a large slaughterhouse in 2010 were inoculated in specific media for S. aureus and methicillin-resistant S. aureus (MRSA) recovery. S. aureus was obtained in 50% of the samples, being all of isolates methicillin-susceptible (MSSA). Genetic lineages, toxin gene profile, and antibiotic resistance mechanisms were determined in recovered isolates. Twenty-five different spa-types were detected among the 50 MSSA with 9 novel spa-types. S. aureus isolates were ascribed to agr type I (37 isolates), III (7), II (4), and IV (2). Sixteen different sequence-types (STs) were revealed by MLST, with seven new ones. STs belonging to clonal clomplex CC133 were majority. The gene tst was detected in 6 isolates and the gene etb in one isolate. Different combinations of enterotoxin, leukocidin and haemolysin genes were identified among S. aureus isolates. The egc-cluster-like and an incomplete egc-cluster-like were detected. Isolates resistant to penicillin, erythromycin, fusidic acid, streptomycin, ciprofloxacin, clindamycin, tetracycline, or chloramphenicol were found and the genes blaZ, erm(A), erm(C), tet(M), fusC were identified. Conclusions The nares of donkeys frequently harbor MSSA. They could be reservoirs of the ruminant-associated CC133 lineage and of toxin genes encoding TSST-1 and other virulence traits with potential implications in public health. CC133 seems to have a broader host distribution than expected.
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Affiliation(s)
- Haythem Gharsa
- Laboratoire des Microorganismes et Biomolécules Actives, Faculté desSciences de Tunis, Université Tunis-El Manar, Tunis 2092, Tunisia
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Tang A, Balzli CL, Caballero AR, McCormick CC, Taylor SD, O'Callaghan RJ. Staphylococcus aureus infection of the rabbit cornea following topical administration. Curr Eye Res 2012; 37:1075-83. [PMID: 22916736 DOI: 10.3109/02713683.2012.716485] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To determine the ability of diverse S. aureus strains to infect the rabbit cornea following topical inoculation, with special emphasis on a strain of unusual virulence. MATERIALS AND METHODS S. aureus strains (5 × 10(5) colony forming units; CFU) were topically applied onto scarified rabbit corneas or 100 CFU were intrastromally injected into rabbit corneas. Eyes were scored by slit lamp examination (SLE) and corneas were cultured to determine the log CFU. Polymorphonuclear leukocytes (PMN) were quantified by myeloperoxidase assays and corneas underwent histopathological analysis. Hemolysin titers of S. aureus strains were determined and S. aureus interactions with rabbit tears or human corneal epithelial cells were investigated. RESULTS All strains injected into the cornea produced high SLE scores and multi-log increases in CFU. Following topical inoculation, four strains produced low SLE scores with no bacterial replication. One strain (UMCR1) topically infected the cornea, causing high SLE scores, extensive PMN infiltration, and multi-log increases in CFU. Histopathologic analysis demonstrated a PMN influx into the UMCR1-infected cornea, destruction of the corneal epithelium, and severe edema. Strain UMCR1 did not demonstrate a high hemolysin titer or resistance to the bactericidal activity of rabbit tears, but did invade human corneal epithelial cells with relatively high efficiency. CONCLUSIONS One S. aureus strain demonstrated the ability to topically infect the rabbit cornea. This strain was previously found to be unique in its ability to infect the anterior chamber and conjunctiva, suggesting that a key mechanism may be employed to overcome the host defenses of these three ocular sites.
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Affiliation(s)
- Aihua Tang
- Department of Microbiology, University of Mississippi Medical Center, Jackson, MS 39216, USA
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Agrawal R, Singh PK, Sharma SK, Kamboj DV, Goel AK, Singh L. Highly Expressed Recombinant SEB for Antibody Production and Development of Immunodetection System. Indian J Microbiol 2012; 52:191-6. [PMID: 23729881 PMCID: PMC3386450 DOI: 10.1007/s12088-011-0173-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Accepted: 03/08/2011] [Indexed: 10/18/2022] Open
Abstract
Staphylococcal enterotoxins (SEs) are the second most common causal agents of food poisoning throughout the world. Staphylococcal enterotoxin B (SEB) is one of the most potent and a listed biological warfare agent. Therefore, its quick, accurate and sensitive detection is of paramount importance. But availability of sensitive and specific antibodies against SEB is the major bottleneck in the development of an immunodetection system. Therefore, in the present study seb gene was cloned and expressed in a heterologous host resulting in a yield of 92 mg pure toxin per litre of culture broth after Ni-NTA affinity purification. Antibodies raised against the recombinant toxin did not cross react with related enterotoxins and organisms that can gain access in the food. Further, a sandwich ELISA was developed to detect SEB after extraction from artificially spiked food samples like milk, orange juice, skim milk and khoya. The sandwich ELISA was able to detect SEB in the range of 0.25 to 0.49 ng/ml or g of food. The detection system developed in the present study is at least as specific and sensitive as other commercially available kits which use monoclonal antibodies.
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Affiliation(s)
- Ranu Agrawal
- Defence Research & Development Establishment, Gwalior, Madhya Pradesh India
| | - Pawan Kumar Singh
- Defence Research & Development Establishment, Gwalior, Madhya Pradesh India
| | | | - D. V. Kamboj
- Defence Research & Development Establishment, Gwalior, Madhya Pradesh India
| | - Ajay Kumar Goel
- Defence Research & Development Establishment, Gwalior, Madhya Pradesh India
| | - Lokendra Singh
- Defence Research & Development Establishment, Gwalior, Madhya Pradesh India
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Sowmya N, Thakur MS, Manonmani HK. Rapid and simple DNA extraction method for the detection of enterotoxigenic Staphylococcus aureus directly from food samples: comparison of PCR and LAMP methods. J Appl Microbiol 2012; 113:106-13. [PMID: 22519925 DOI: 10.1111/j.1365-2672.2012.05315.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
AIMS The study describes the development of simple and rapid DNA extraction method in combination with loop-mediated isothermal amplification (LAMP) to detect enterotoxigenic Staphylococcus aureus in food samples. METHODS AND RESULTS In this study, isolation of genomic DNA of enterotoxigenic Staph. aureus from spiked milk, milk burfi, khoa, sugarcane juice and boiled rice was carried out by boiling the isolated sample pellets for 10 min with 1% Triton X-100. The isolated DNA was evaluated by polymerase chain reaction (PCR) and LAMP method. The LAMP was found to be 100 times more sensitive than PCR. The LAMP assay was very specific for Staph. aureus, and the presence of other contaminating bacterial DNAs and food matrix did not interfere or inhibit the LAMP assay. CONCLUSIONS The template DNA extraction method developed in this study for food samples is simple, rapid and cost-effective. LAMP was found to be less sensitive to matrix effect of food, compared to PCR. SIGNIFICANCE AND IMPACT OF THE STUDY The method is suitable for direct detection of Staph. aureus without any enrichment in contaminated food samples and hence finds its application in food safety analysis, in permutation with LAMP.
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Affiliation(s)
- N Sowmya
- Fermentation Technology and Bioengineering Department, Central Food Technological Research Institute (CSIR), Mysore, Karnataka, India
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Linage B, Rodríguez-Calleja J, Otero A, García-López M, Santos J. Characterization of coagulase-positive staphylococci isolated from tank and silo ewe milk. J Dairy Sci 2012; 95:1639-44. [DOI: 10.3168/jds.2011-4734] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Accepted: 11/30/2011] [Indexed: 11/19/2022]
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Oliveira L, Rodrigues AC, Hulland C, Ruegg PL. Enterotoxin production, enterotoxin gene distribution, and genetic diversity of Staphylococcus aureus recovered from milk of cows with subclinical mastitis. Am J Vet Res 2012; 72:1361-8. [PMID: 21962279 DOI: 10.2460/ajvr.72.10.1361] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate enterotoxin production, enterotoxin gene distribution, and genetic diversity of Staphylococcus aureus in milk obtained from cows with subclinical mastitis. SAMPLE Milk samples obtained from 350 cows (1,354 mammary glands) on 11 Wisconsin dairy farms. PROCEDURES Of 252 S aureus isolates obtained from 146 cows, 83 isolates (from 66 cows with subclinical mastitis) were compared genotypically by use of pulsed-field gel electrophoresis and via PCR identification of toxic shock syndrome toxin 1 (TSST-1) and classical S aureus enterotoxin genes (sea, seb, sec, sed, and see). RESULTS Among the 83 S aureus isolates, ≥ 1 enterotoxin genes were identified in 8 (9.6%). Enterotoxin gene distribution was as follows: TSST-1, 7 isolates (8.4%); sec, 5 isolates (6.0%); and sed, 2 isolates (2.4%). Enterotoxin genes sea, seb, and see were not identified. Twelve pulsotypes and 5 subtypes were identified among the 83 isolates; 5 of the 12 pulsotypes were represented by only 1 isolate. In cows of 1 herd, only a single S aureus pulsotype was detected; in cows on most other farms, a variety of pulsotypes were identified. One pulsotype was recovered from 4 farms (n = 23 cows) and another from 5 other farms (16). Isolates with an enterotoxin gene were represented by 6 pulsotypes. CONCLUSIONS AND CLINICAL RELEVANCE S aureus classical enterotoxins and TSST-1 were rarely recovered from milk samples obtained from cows with subclinical mastitis in Wisconsin. Diverse pulsotypes of S aureus were detected within and among farms, indicating that different strains of S aureus cause subclinical mastitis in dairy cows.
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Affiliation(s)
- Leane Oliveira
- Department of Dairy Science, College of Agriculture and Life Sciences, University of Wisconsin, Madison, WI 53706, USA
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Wan M, Fu S, Lo Y, Huang T, Cheng M, Chou C. Heterogeneity and phylogenetic relationships of community-associated methicillin-sensitive/resistant Staphylococcus aureus isolates in healthy dogs, cats and their owners. J Appl Microbiol 2011; 112:205-13. [DOI: 10.1111/j.1365-2672.2011.05179.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Wilson GJ, Seo KS, Cartwright RA, Connelley T, Chuang-Smith ON, Merriman JA, Guinane CM, Park JY, Bohach GA, Schlievert PM, Morrison WI, Fitzgerald JR. A novel core genome-encoded superantigen contributes to lethality of community-associated MRSA necrotizing pneumonia. PLoS Pathog 2011; 7:e1002271. [PMID: 22022262 PMCID: PMC3192841 DOI: 10.1371/journal.ppat.1002271] [Citation(s) in RCA: 136] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Accepted: 08/01/2011] [Indexed: 01/08/2023] Open
Abstract
Bacterial superantigens (SAg) stimulate T-cell hyper-activation resulting in immune modulation and severe systemic illnesses such as Staphylococcus aureus toxic shock syndrome. However, all known S. aureus SAgs are encoded by mobile genetic elements and are made by only a proportion of strains. Here, we report the discovery of a novel SAg staphylococcal enterotoxin-like toxin X (SElX) encoded in the core genome of 95% of phylogenetically diverse S. aureus strains from human and animal infections, including the epidemic community-associated methicillin-resistant S. aureus (CA-MRSA) USA300 clone. SElX has a unique predicted structure characterized by a truncated SAg B-domain, but exhibits the characteristic biological activities of a SAg including Vβ-specific T-cell mitogenicity, pyrogenicity and endotoxin enhancement. In addition, SElX is expressed by clinical isolates in vitro, and during human, bovine, and ovine infections, consistent with a broad role in S. aureus infections of multiple host species. Phylogenetic analysis suggests that the selx gene was acquired horizontally by a progenitor of the S. aureus species, followed by allelic diversification by point mutation and assortative recombination resulting in at least 17 different alleles among the major pathogenic clones. Of note, SElX variants made by human- or ruminant-specific S. aureus clones demonstrated overlapping but distinct Vβ activation profiles for human and bovine lymphocytes, indicating functional diversification of SElX in different host species. Importantly, SElX made by CA-MRSA USA300 contributed to lethality in a rabbit model of necrotizing pneumonia revealing a novel virulence determinant of CA-MRSA disease pathogenesis. Taken together, we report the discovery and characterization of a unique core genome-encoded superantigen, providing new insights into the evolution of pathogenic S. aureus and the molecular basis for severe infections caused by the CA-MRSA USA300 epidemic clone. Staphylococcus aureus is a global pathogen, responsible for an array of different illnesses in humans and animals. In particular, community-associated methicillin-resistant S. aureus (CA-MRSA) strains of the pandemic USA300 clone have the capacity to cause lethal human necrotizing pneumonia, but the molecular basis for the enhanced virulence remains unclear. Bacterial superantigens (SAg) stimulate T-cell hyper-activation resulting in severe systemic illnesses such as toxic shock syndrome (TSS). However, all S. aureus SAgs identified to date are encoded by mobile genetic elements found only in a proportion of clinical isolates. Here, we report the discovery of a unique core genome-encoded SAg (SElX) which was acquired by an ancestor of the S. aureus species and which has undergone genetic and functional diversification in pathogenic clones infecting humans and animals. Importantly, we report that SElX made by pandemic USA300 contributes to lethality in a rabbit model of human necrotizing pneumonia revealing a novel virulence determinant of severe CA-MRSA infection.
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Affiliation(s)
- Gillian J. Wilson
- The Roslin Institute and Centre for Infectious Diseases, University of Edinburgh, Easter Bush Campus, Midlothian, United Kingdom
| | - Keun Seok Seo
- Department of Basic Sciences, Mississippi State University, Mississippi State, Mississippi, United States of America
| | - Robyn A. Cartwright
- The Roslin Institute and Centre for Infectious Diseases, University of Edinburgh, Easter Bush Campus, Midlothian, United Kingdom
| | - Timothy Connelley
- The Roslin Institute and Centre for Infectious Diseases, University of Edinburgh, Easter Bush Campus, Midlothian, United Kingdom
| | - Olivia N. Chuang-Smith
- Department of Microbiology, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America
| | - Joseph A. Merriman
- Department of Microbiology, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America
| | - Caitriona M. Guinane
- The Roslin Institute and Centre for Infectious Diseases, University of Edinburgh, Easter Bush Campus, Midlothian, United Kingdom
| | - Joo Youn Park
- Department of Basic Sciences, Mississippi State University, Mississippi State, Mississippi, United States of America
| | - Gregory A. Bohach
- Department of Basic Sciences, Mississippi State University, Mississippi State, Mississippi, United States of America
- Department of Biochemistry and Molecular Biology, Mississippi State University, Mississippi State, Mississippi, United States of America
| | - Patrick M. Schlievert
- Department of Microbiology, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America
| | - W. Ivan Morrison
- The Roslin Institute and Centre for Infectious Diseases, University of Edinburgh, Easter Bush Campus, Midlothian, United Kingdom
| | - J. Ross Fitzgerald
- The Roslin Institute and Centre for Infectious Diseases, University of Edinburgh, Easter Bush Campus, Midlothian, United Kingdom
- * E-mail:
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46
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Tokajian S, Haddad D, Andraos R, Hashwa F, Araj G. Toxins and Antibiotic Resistance in Staphylococcus aureus Isolated from a Major Hospital in Lebanon. ISRN MICROBIOLOGY 2011; 2011:812049. [PMID: 23724312 PMCID: PMC3658828 DOI: 10.5402/2011/812049] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Accepted: 07/21/2011] [Indexed: 11/23/2022]
Abstract
Molecular characterization of Staphylococcus aureus is of both clinical and infection control importance. Virulence determinants using PCR and multiple drug resistance profiles were studied in 130 S. aureus isolates. PCR-RFLP analysis of the 16S-23S DNA spacer region was done to investigate the level of 16S-23S ITS (internal transcribed spacer) polymorphism. Methicillin-resistant S. aureus (MRSA), which represented 72% of the studied isolates, showed multiple drug resistance with 18% being resistant to 10-18 of the drugs used compared to a maximum resistance to 9 antibiotics with the methicillin sensitive S. aureus (MSSA) isolates. Exfoliative toxin A (ETA) was more prevalent than B (ETB) with virulent determinants being additionally detected in multiple drug-resistant isolates. 16S-23S ITS PCR-RFLP combined with sequencing of the primary product was successful in generating molecular fingerprints of S. aureus and could be used for preliminary typing. This is the first study to demonstrate the incidence of virulent genes, ACME, and genetic diversity of S. aureus isolates in Lebanon. The data presented here epitomize a starting point defining the major genetic populations of both MRSA and MSSA in Lebanon and provide a basis for clinical epidemiological studies.
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Affiliation(s)
- Sima Tokajian
- Genomics and Proteomics Research Laboratory, Department of Biology, Lebanese American University, P.O. Box 36, Byblos, Lebanon
| | - Dominik Haddad
- Genomics and Proteomics Research Laboratory, Department of Biology, Lebanese American University, P.O. Box 36, Byblos, Lebanon
| | - Rana Andraos
- Genomics and Proteomics Research Laboratory, Department of Biology, Lebanese American University, P.O. Box 36, Byblos, Lebanon
| | - Fuad Hashwa
- Genomics and Proteomics Research Laboratory, Department of Biology, Lebanese American University, P.O. Box 36, Byblos, Lebanon
| | - George Araj
- Department of Pathology and Laboratory Medicine, American University of Beirut Medical Centre, Beirut, Lebanon
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47
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Lozano C, Gómez-Sanz E, Benito D, Aspiroz C, Zarazaga M, Torres C. Staphylococcus aureus nasal carriage, virulence traits, antibiotic resistance mechanisms, and genetic lineages in healthy humans in Spain, with detection of CC398 and CC97 strains. Int J Med Microbiol 2011; 301:500-5. [DOI: 10.1016/j.ijmm.2011.02.004] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Revised: 12/22/2010] [Accepted: 02/22/2011] [Indexed: 10/18/2022] Open
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48
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Oh SK, Koo M, Lee N, Kim HJ, Oh SW, Choi SY. Distribution of newly described enterotoxin-like genes in Staphylococcus aureus isolated from ready-to-eat foods in Korea. Food Sci Biotechnol 2011. [DOI: 10.1007/s10068-011-0082-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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49
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Prevalence of toxicogenic bacteria in some foods and detection of Bacillus cereus and Staphylococcus aureus enterotoxin genes using multiplex PCR. ANN MICROBIOL 2011. [DOI: 10.1007/s13213-011-0293-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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50
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Abdel-moein KA, Samir A. Isolation of EnterotoxigenicStaphylococcus aureusfrom Pet Dogs and Cats: A Public Health Implication. Vector Borne Zoonotic Dis 2011; 11:627-9. [DOI: 10.1089/vbz.2010.0272] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
| | - Ahmed Samir
- Department of Microbiology, Faculty of Veterinary Medicine, Cairo University, Cairo, Egypt
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