Isolation, identification and characterization of Staphylococcus sp. from Indian ethnic fermented fish product

Staphylococci fromSheedalof Northeast India was isolated, identified and characterized. All the isolated staphylococci were found to be coagulase negative. Based on therpoBgene sequences followed by analysis using NCBI-BLAST software, seven species ofStaphylococcusnamely,S. piscifermentans,S. condimenti,S. arlettae,S. sciuri,S. warneri,S. nepalensisandS. hominiswere recognized. Phylogenetic analyses revealed three major cluster groups. All the sevenStaphylococcusshowed their NaCl tolerance from 2 to 8%. No species was able to grow at 55 degrees C. ExceptS. arlettaeandS. sciuri, all the isolated staphylococcal species exhibited growth at pH 4-8. No isolated species was able to ferment mannitol, sucrose and arabinose. All the species exhibited moderate to maximum proteolytic and lipolytic activities. All the seven species were found to be sensitive to the antibiotics, namely, erythromycin, norfloxacin, ampicillin, streptomycin and vancomycin, whereas all were resistant to co-trimoxazole. OnlyS. piscifermentanswas found antagonist toSalmonella enterica,Escherichia coliandBacillus subtilis, although the clear zone was minimal. All the staphylococcal species exceptS. arlettaeandS. sciuriexhibited hydrophobicity ranging from 25 to 66%. The observed characteristics of isolated Staphylococci fromSheedalrevealed their role in fish fermentation.