Isolation and characterisation of Staphylococcus aureus strains isolated from beef, sheep and chicken meat

Abstract

The objective of this study was to evaluate the occurrence, enterotoxigenic properties and antibiotic resistance of Staphylococcus aureus in beef, sheep and chicken meat. For this purpose, 225 meat samples were obtained from different supermarkets in Ankara. Firstly, these samples were analysed phenotypically for coagulase-positive staphylococci and S. aureus. Then phenotypically determined S. aureus isolates were confirmed through PCR assay and investigated by multiplex PCR for enterotoxin genes and mecA gene. According to the analyses, 14.6%, 30.6% and 45.3% of the beef, sheep and chicken meat samples respectively were found to be contaminated with S. aureus. Eighty eight (77.1%) out of 114 S. aureus isolates were determined as enterotoxigenic. Also, isolates contained newly described enterotoxin like genes. These results indicated that new types enterotoxin genes could be effective in establishing food intoxication. In this study, isolates were found resistant to one or more antibiotics. None of the S. aureus isolates contain mecA gene but some of them were identified as resistant to a group of antibiotics like oxacillin and cefoxitin, which are used in determining methicillin resistance. For public health and hygienic meat production HACCP and GMP systems should be implemented effectively

Keywords

• Enterotoxin
• meat
• mecA
• PCR
• Staphylococcus aureus

Sığır, koyun ve piliç etlerinden Staphylococcus aureus’un izolasyon ve karakterizasyonu

Abstract

Bu çalışma sığır, koyun ve piliç etlerinde Staphylococcus aureus’un bulunuşu, enterotoksijenik özellikleri ve antibiyotik dirençliliklerini saptamak amacıyla yapılmıştır. Bu amaçla, Ankara’daki farklı süpermarketlerden 225 adet et örneği alınmıştır. Alınan örnekler öncelikle koagulaz-pozitif stafilokoklar ve S. aureus yönünden analiz edilmiştir. Fenotipik testler sonucu S. aureus olarak belirlenen suşlar PCR tekniği ile doğrulanarak, multipleks PCR tekniği kullanılarak enterotoksin genleri ve mecA geni yönünden analiz edilmiştir. Analiz sonuçlarına göre sığır, koyun ve piliç eti örnekleri S. aureus ile sırasıyla % 14.6, % 30.6 ve % 45.3 düzeyinde kontamine bulunmuştur. İzole edilen 114 adet S. aureus izolatından 88’inin (% 77.1) enterotoksijenik özellikte olduğu tespit edilmiştir. İzolatların yeni tanımlanan enterotoksin genlerine sahip oldukları belirlenmiştir. Sonuçlar, yeni tanımlanan enterotoksin genlerinin gıda intoksikasyonlarında önemli olabileceğini ortaya koymaktadır. Bu çalışmada izolatlar bir veya daha fazla antibiyotiğe dirençli bulunmuştur. S. aureus izolatlarının hiçbirinde mecA geni saptanmamasına karşın, bazı izolatlar metisilin duyarlılığının belirlenmesinde kullanılan, oxacillin ve cefoxitine dirençli bulunmuştur. Halk sağlığının korunması ve hijyenik et üretimi için HACCP ve GMP sistemlerinin etkin uygulanması önemlidir

Keywords

• Enterotoksin
• et
• mecA
• PCR
• Staphylococcus aureus

References

1. Akineden O, Hassan AA, Schneider E, et al. (2008): Enterotoxigenic properties of Staphylococcus aureus isolated from goats’milk cheese. Int J Food Microbiol, 124, 211-216.
2. Arcuri EF, Angelo FF, Guimarães MF, et al. (2010): Toxigenic status of Staphylococcus aureus isolated from bovine raw milk and Minas frescal cheese in Brazil. J Food Prot, 73, 2225-2231.
3. Bhargava K, Wang X, Donabedian S, et al. (2011): Methicillin-resistant Staphylococcus aureus in retail meat, Detroit, MI, USA. Emerg Infect Dis, 17, 1135-1137.
4. Brakstad OG, Aasbakk K, Maeland JA (1992): Detection of Staphylococcus aureus by polymerase chain reaction amplification of the nuc gene. J Clin Microbiol, 30, 1654-1660. CO, 5. Gill Badoni M, McGinnis JC (2001): Microbiological sampling of meat cuts and manufacturing beef by excision or swabbing. J Food Prot, 64, 325-334.
5. Hanson BM, Dressler AE, Harper AL, et al. (2011): Prevalence of Staphylococcus aureus and methicillin- resistant Staphylococcus aureus (MRSA) on retail meat in Iowa. J Infec Public Health, 4, 169-174.
6. International Standard Office (2003): Microbiology of food and animal feeding stuffs - horizontal method for the enumeration of coagulase-positive staphylococci, EN ISO 6888-1 (Staphylococcus aureus and other species).
7. Jarraud S, Cozon G, Vandenesch F, et al. (1999): Involvement of enterotoxins G and I in staphylococcal toxic shock syndrome and staphylococcal scarlet fever. J Clin Microbiol, 37, 2446-2449.
8. Johnson, WM, Tyler SD, Ewan EP, et al. (1991): Detection of genes for enterotoxins, exfoliative toxins, and toxic shock syndrome toxin 1 in Staphylococcus aureus by the polymerase chain reaction. J Clin Microbiol, 29, 426-430.

9. Kelman A, Soong YA, Dupuy N, et al. (2011): Antimicrobial susceptibility of Staphylococcus aureus from retail ground meats. J Food Prot, 74, 1625-1629.
10. Kitai S, Shimizu A, Kawano J, et al. (2005): Characterization of methicillin-resistant S. aureus isolated from retail raw chicken meat in Japan. J Vet Med Sci, 67, 107-110.
11. Kluytmans J, Van Belkum A, Verbrugh H (1997): Nasal carriage of Staphylococcus aureus: Epidemiology, underlying mechanisms, and associated risks. Clin Microbiol Rev, 10, 505-520.
12. Koc HI, Ozdemir H (2013): Determination of microbial surface contamination on lamb carcasses. J Turk Vet Med Society, 84, 19-25.
13. Kuzma K, Malinowskie E, Lassa H, et al. (2003): Detection of genes for enterotoxins and toxic shock syndrome toxin-1 in Staphylococcus aureus isolated from bovine mastitis. Bull Vet Inst Pulawy, 47, 419-426. 15. Lee JH (2003): Methicillin Staphylococcus aureus strains isolated from major food animals and their potential transmission to humans. Appl Environ Microbiol, 69, 6489-6494.
14. (oxacillin)-resistant
15. Le Loir Y, Baron F, Gautier M (2003): Staphylococcus aureus and food poisoning. Gen Mol Research, 2, 63-67.
16. Lim SK, Nam HM, Park HJ, et al. (2010): Prevalence and Staphylococcus aureus in raw meat in Korea. J Microbiol Biotech, 20, 775-778. of methicillin resistant 18. Livermore DM (2000): staphylococci. Int J Antimicrobial Agents, 16, 3-10. Antibiotic resistance in Ankara, Turkey.