Phenotypic Detection of AAC(6 ′)-Ib-Cr Expression in Enterobacteriacae Isolates
| Autor: | Sanjeev Das, Manas Bandyopadhyay, Mitali Chatterjee, Prabir Mukhopadhyay, Sumon Poddar, Maitreyi Bandyopadhyay, Simit Kumar |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
0301 basic medicine
biology medicine.drug_class business.industry 030106 microbiology Drug resistance biochemical phenomena metabolism and nutrition bacterial infections and mycoses biology.organism_classification Quinolone Enterobacteriaceae Microbiology Agar plate Ciprofloxacin 03 medical and health sciences medicine bacteria Agar diffusion test Efflux business Norfloxacin medicine.drug |
| Zdroj: | IOSR Journal of Dental and Medical Sciences. 15:85-90 |
| ISSN: | 2279-0853 2279-0861 |
| DOI: | 10.9790/0853-1508068590 |
| Popis: | Background: Quinolone resistance in Enterobacteriaceae usually results from mutations in genes carried by chromosomally encoded type II topoisomerases, efflux pumps, or porin-related proteins. Since 1998, plasmid-mediated quinolone resistances (PMQR) have been described. Recently, a new mechanism of transferable quinolone resistance was reported: enzymatic inactivation of certain quinolones. AAC(6′)-Ib-cr is a variant of AAC(6′)-Ib which encodes an aminoglycoside acetyltransferase that confers reduced susceptibility to ciprofloxacin or norfloxacin.. PMQR determinants are often combined with extended-spectrum beta-lactamases (ESBLs) leading to organisms possessing multi drug resistance. Aims & Objectives: To study the incidence of AAC(6′)-Ib-cr expression in Enterobacteriacae isolates by phenotypic method and to find any correlation between the genetic expression of AAC(6′)-Ib-cr along with ESBL production. Materials and methods: The 430 clinical Enterobacteriaceae isolates exhibiting ciprofloxacin and norfloxacin resistance were included in this study. They were grown in Luria-Bertani Broth ( LB broth) containing norfloxacin (8 µg/ml), with intermittent shaking for 18 h at 35°C. Ten microliters of each culture medium was applied on the blank disk set on a Mueller-Hinton agar plate inoculated with E. coli ATCC 25922 and incubated for 18 h at 35°C. A significant decrease of a growth-inhibitory zone by ≥ 10 mm was considered as a positive test for the production of aac(6′)-Ib-cr, while aac(6′)-Ib-cr production was considered not to be produced in strains which did not show any reduction in the zone of inhibition. Results: The overall expression of the AAC(6′)-Ib-cr did not show much variation with almost half of the isolates from all the different samples showing AAC(6′)-Ib-cr production with blood isolates showing a production as high as 66.77%.). A significant association was noted with ESBL production and the simultaneous expression of AAC(6′)-Ib-cr in both E.coli (P value |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|