Vol. 11, Special Issue 7 (2022)

Author(s):
Basant, BN Shringi, AK Pandey, Parma Ram Gorachiya and Sudesh Kumar

Abstract:
Antibiotics have been used in large amount for treating mild to severe microbial infection since their introduction in early 20^th century but in present scenario a worrying and serious condition is the emergence of multidrug resistant strains of most common infectious microbes due to huge and unmonitored use of antibiotics. There is an urgent need to discover some therapeutic agents that can increase the potency of commonly used antibiotics. The present study aimed to designing and in vitro testing of synthetic peptides on the basis of protein sequence and structure of AcrAB-TolC, is a commonly expressed efflux pump of Escherichia coli (E. coli). SG-15 was designed as inner membrane protein (AcrB) blocker. A 10 E. coli isolates were obtained from 28 clinical mastic milk samples. Proteomic based characterization of isolates performed using VITEK MS RUO (Research Use Only) and genotypic characterization was done using PCR. After proteomic and genotypic confirmation of isolates antibiotic susceptibility testing was done as per the disc diffusion method and efflux activity was estimated by cartwheel method. More than half of the isolates exhibited resistance to multiple antibiotics and all the isolates showed varying degree of efflux activity. After that activity of synthetic peptide SG-15 tested alone and also in combination with antibiotics namely gentamicin, ampicillin, and cephalothin from which some combination exhibited significant synergistic effect.