ISOLATION AND CHARACTERIZATION OF MULTIDRUG RESISTANT BETA-LACTAMASE PRODUCING SALMONELLA ENTERICA FROM WILD MIGRATORY BIRDS
Applied Ecology and Environmental Research
A multidrug resistant, an enteric pathogen, Salmonella enterica is the most frequent cause of food poisoning. They are gram negative, aerobic or facultative anaerobic bacteria belonging to the family Enterobacteriacae. Migratory birds serve as key factor, may disseminate Salmonella to the susceptible people through shared environment, fecal shedding and by mean of direct contact. The aim of present study was to investigate the occurrence of beta-lactamase genes (CTX-M and TEM) within antibiotic
... ) within antibiotic resistant strains of Salmonella enterica isolated from migratory birds. Present study incorporated isolation of 60 samples of Salmonella enterica from saliva, intestinal fluid and blood of different migratory birds. They are catalase positive, oxidase negative and H2S gas producer. The antibiotic resistance of all isolated strains (29) was tested against 10 antibiotics by Kirby-Bauer disc diffusion method. The antibiotics that were used include ciprofloxacin (5 µg), ceftriaxone (30 µg), meropenam (10 µg), aztreonam (30 µg), penicillin (10 µg), erythromycin (15 µg), streptomycin (10 µg), gentamycin (10 µg), vancomycin (10 µg) and imipenem (10 µg). These strains indicated more resistance towards penicillin (93%), streptomycin (100%), erythromycin (93%), aztreonam (62%) and vancomycin (90%) and low resistance towards ciprofloxacin (21%), ceftriaxone (54%) and imepenam (45%). For the detection of CTX-M and TEM gene in ciprofloxacin and ceftriaxone resistant strains, DNA was obtained through chemical method. These strains were further checked for the presence of CTX-M and TEM gene by polymerase chain reaction (PCR). PCR results demonstrated that all the strains contain TEM gene but CTX-M gene was not identified in any of these strains. PCR amplified product was sequenced, followed by BLAST, which confirmed the presence of TEM gene giving resistance to beta-lactam antibiotics.