Molecular screening of staphylococcal enterotoxin type P encoding gene from clinical isolates

Abstract

Background: In recent years, the roles of Staphylococcal enterotoxins in the non-gastrointestinal diseases have been reported. The most frequently mentioned was enterotoxin type A. But in many cases there are also high similarity with type P. Accordingly, the differentiation of producing enterotoxin type P strains from type A is essential. Objectives: The objective of this study was to assess and characterize Staphylococcus aureus containing entP gene from infectious specimens. Materials and Methods: Based on the reference sequence (S. aureus N315 entP gene), pair primers were designed. 350 clinical strains of S. aureus were assessed by polymerase chain reaction (PCR). The purifed PCR product was sequenced. All isolated S. aureus strains containing the entP gene were tested by Enzyme immunoassay. Results: The PCR amplification method was optimized for entP gene detection. The used primer pairs were amplified for 213 bp and 700 bp fragment separately. The sequencing results indicate that only 98 (28%) out of the 350 strains of S. aureus contained entP gene. The results of Enzyme immunoassay test for enterotoxins detection revealed that 79 (22.57%) of the strains contained entP gene were which also produced other enterotoxins (such as enterotoxin A to E) and 19 (5.43%) of the strains were carriers of only enterotoxin P gene unable to produce other enterotoxins. Conclusions: The results revealed, the specific primers that amplified the entE gene were able to amplify the Staphylococcal Enterotoxin-Like Toxin Type P gene. The specific primers for the entP gene were amplifed a fragmented gene (700 bp) showed 100% homology with entP reference gene and also 80% homology with entA and entE genes. © 2013, Ahvaz Jundishapur University of Medical Sciences; Licensee Kowsar Ltd.