title: Characterization of Staphylococcus aureus isolates from white-brined Urfa cheese.
abstract: The aim of this study was to investigate the presence of Staphylococcus aureus and staphylococcal enterotoxin (SE) genes in Urfa cheese samples and to characterize the enterotoxigenic potential of these isolates. From a total of 127 Urfa cheese samples, 53 isolates (from 41.7%  of the samples) were identified by a species-specific PCR assay as S. aureus. Of these isolates, 40 (75.5%) gave positive PCR results for the 3' end of the coa gene. The coa-positive S. aureus strains were characterized for their population levels and enterotoxigenic  properties, including slime factor, β-lactamase, antibiotic susceptibilities, production of the classical SEs (SEA through SEE), in both cheese and liquid cultures by enzyme-linked immunosorbent assay (ELISA) and for the presence of specific genes, including classical SE genes (sea  through see), mecA, femA, and spa, by PCR. The genetic relatedness among the coa-positive S. aureus isolates was investigated by PCR-based restriction fragment length polymorphism (RFLP) analysis and the 23S rRNA gene spacer. The 23S rRNA gene spacer and  coa RFLP analysis using AluI and Hin6I revealed 14 different patterns. SEB, SEC, and SEA and SEE were detected by ELISA in three cheese samples. Fourteen S. aureus strains harbored enterotoxin genes sea through see, and three strains carried multiple  toxin genes. The most commonly detected toxin gene was sec (25% of tested strains). Of the 40 analyzed S. aureus strains, 3 (7.5%) were mecA positive. Based on tandem repeats, four coa and spa types were identified. The results of this study indicate that  S. aureus and SEs are present at significant levels in Urfa cheese. These toxins can cause staphylococcal food poisoning, creating a serious hazard for public health.
authors: Department of Microbiology, Faculty of Veterinary Medicine, University of Selcuk, Campus, 42075 Selcuklu, Konya, Turkey.
authors: Kursat
authors: K
authors: Kav
authors: Ramazan
authors: R
authors: Col
authors: Mustafa
authors: M
authors: Ardic
mesh_terms: D001427:Bacterial Toxins / Q000032:analysis / Q000235:genetics; D002611:Cheese / Q000382:microbiology*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004768:Enterotoxins; D005506:Food Contamination / Q000032:analysis*; D006801:Humans; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D012338:RNA, Ribosomal, 23S / Q000737:chemistry / Q000235:genetics; D013045:Species Specificity; D013202:Staphylococcal Food Poisoning / Q000517:prevention & control; D013211:Staphylococcus aureus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*
chemical_list: D001427:Bacterial Toxins; D004269:DNA, Bacterial; D004768:Enterotoxins; D012338:RNA, Ribosomal, 23S