Ecology, Environment and Conservation Paper

ISOLATION AND MOLECULAR CHARACTERIZATION OF EXTENDED SPECTRUM β β β β β-LACTAMASE PRODUCING ESCHERICHIA COLI AND KLEBSIELLA PNEUMONIAE FROM SOIL SAMPLES OF HOSPITAL ENVIRONMENT IN CHENNAI, INDIA

A. Helen, Sulochana Somasundaram, A.S. Smiline Girija and J. Vijayashree Priyadarshini

Abstract

The propagation of extended-spectrum β-lactamase (ESBL) producing Escherichia coli and Klebsiella pneumoniae from hospital waste to the surrounding environment engrossed greater awareness. The endeavour of the present study is to demonstrate the prevalence and molecular characterization of ESBL producing Escherichia coli and Klebsiella pneumoniae from soil samples. Isolates from soil samples were screened for ESBL production by antimicrobial sensitivity test using disc diffusion method and phenotypic identification by combination disc method as recommended by CLSI 2011. Besides confirmation of potential ESBL producer’s was detected in the Hi-Chrome ESBL Agar. Recognition of resistant genes such as TEM, SHV and CTX-M from phenotypically confirmed resistant strains was done by following PCR. Among the total isolates (N=600; n=63) 10.5% was confirmed as potential ESBL producers, from the 30 soil samples tested from six different sites in which 15% (n=46) was E. coli and 5% (n=17) was K. pneumoniae. Among all the three ESBL genetic determinants, CTX-M (30%) and SHV (94%) genes were more prevalent in E.coli and K. pneumoniae respectively. The above findings have shown that ESBL-producing Escherichia coli and Klebsiella pneumoniae are exhibiting multidrug resistance property circulating with possibility of dissemination in the surrounding environment and community.