Prevalence and Characterization of Coagulase Positive Staphylococci Isolated from Salted Anchovy

Abstract

A total of 100 salted anchovy samples were used to investigate the prevalence of S. aureus and other coagulase positive Staphylococci (CPS) as well as to determine the methicillin (MR) and antibiotic resistance (AR) profile, the presence of Panton-Valentine leukocidine (PVL) toxin gene (lukS/F-PV), slime factor properties (SFP), and the genotypic relatedness of the isolates. Agar disc diffusion assay (ADDA) and microdilution broth susceptibility test (MDBST) were applied to compare the specificity and sensitivity of the MR detection methods. A total of 41 CPS isolates were detected at the 10² and 10³ CFU/g levels in contrast to S. aureus. The 16S rRNA (genus specific) was detected in all the isolates in contrast to nuc (species-specific) and lukS/F-PV genes. A total of 16/41 isolates were found to be MR by using the three methods. Polymerase chain reaction (PCR) assay was a more sensitive and reliable method for the detection of MR isolates. The antibiotic resistance rates were 75.60, 73.17, 51.21, 31.70, 12.19, and 4.87% to penicillin, ampicillin, tetracycline, erythromycin, ciprofloxacin, and clindamycin, respectively. All the isolates were sensitive to gentamicin and vancomycin. The SFP were determined in all the isolates by using Congo Red agar, and 20 different genotypes were determined by using randomly amplified polymorphic DNA (RAPD)-PCR assay.

Keywords:

• coagulase positive Staphylococci
• S. aureus
• salted anchovy
• antibiotic resistance
• methicillin resistance
• biofilm
• PVL
• genotyping

Notes

Some parts of the article were submitted to The 3rd Global Fisheries and Aquaculture Research Conference, Egypt, Proceeding for Middle East & North Africa Journal of Animal Science, Issue No. 12962, Vol. No. 2, pp. 144–158, 2010, November 29–December 1, Foreign Agricultural Relations (FAR), Dokki-Giza, Egypt, 2010.