Detection of Chromosomal AmpC, blaCTX-M in Extended Spectrum Beta Lactamase Producing Eschericha coli in Seafood Processing Effluent

Abstract

The higher incidence of extended spectrum of beta lactamase (ESBL) producing Escherichia coli (E. coli) in various community triggers to investigate the ESBL prevalence in seafood and its environment. A total of 24 fish processing effluent samples were collected fortnightly during January 2015–Dec 2015 and screened for ESBL producing E. coli. Twenty-eight E. coli strains were subjected to antibiogram and minimum inhibitory concentration. The ESBL production was tested using ready-made Brilliance ESBL agar (# PO5302, Oxoid) and ready to use minimum inhibition concentration (MIC) strips, Triple ESBL detection Ezy MICTM strip and ESBL and AmpC detection strip. Out of 28 isolates, four isolates of E. coli were confirmed as ESBL producers and expressed resistance to antimicrobial agents like Cefuroxime, Amoxyclav, Ceftizoxime, Cefotaxime and Cefoperazone. Multiplex polymerase chain reaction (PCR) assay confirmed the genes responsible for resistance were blaCTX-M families (592 bp) and Chromosomal AmpC (191 bp). The CTX-M genes have the ability to hydrolyze the Cefotoxime and Ceftazidime antimicrobials and are currently one of the largest groups of beta-lactamases. AmpC gene can be chromosomal or plasmid mediated and confers resistance to Cephalothin, Cefazolin, Cefoxitin and it also mediates resistance to beta-lactamase inhibitors. The present investigation shows proliferation of clinically evolved multi drug resistant bacteria such as ESBL producing E. coli into non clinical settings such as fisheries. It is further suggested that fecal contamination as well as unhygienic treatment of fish processing waste followed by disposal to the surrounding environment may act as the potential source of contamination.