Phenotypic and genotypic detection of the virulence factors and their association with antibiotic resistance inEnterococcusspecies

Abstract

Abstract-Along with the emergence of drug resistantEnterococcalinfection, role of various virulence factors inEnterococciis an emerging concept. A number of virulence factors like biofilm formation, hemolysin production, gelatin hydrolysis have important role in the pathogenesis ofEnterococciand also associated with antibiotic resistance. The aim of our study was to detect the virulence factors and their encoding genes (asa, gelE, esp, ebpR, hylgene for biofilm;cylAgene for hemolysis;gelEgene for gelatin hydrolysis) and also observe their association with antimicrobial resistanceEnterococci. A total of 87Enterococciwere collected from different clinical samples. Virulence factors were detected phenotypically and antibiotic sensivity were done by Kirby Bauer disc diffusion method. Virulence genes were detected by conventional multiplex PCR and only theebpRgene was detected by single conventional PCR. Majority of the isolatedEnterococciwereE. faecalis(75%) followed byE. faecium(23%) and (2%)E. raffinosuswere also detected. About 52.3% ofE. faecalisand 35% ofE. faeciumisolates were biofilm producers. Significant association was found between biofilm formation andasa, esp, ebpRgenes both inE. faecalisand inE. faecium.Hemolysis was observed phenotypically in 30.8% isolates ofE. faecalisand 20% isolates ofE. faecium. Significant association was observed betweencylAgene and hemolysin production inE. faecalis. Antibiotic resistance were higher in biofilm and hemolysin producing isolates of both species. Resistance to some antibiotics including ampicillin, ciprofloxacin, gentamicin were significantly higher among biofilm and hemolysin producer inE. faecalis.