Molecular Analysis of Selected Resistance Determinants in Diarrheal Fecal Samples Collected From Kolkata, India Reveals an Abundance of Resistance Genes and the Potential Role of the Microbiota in Its Dissemination

Abstract

study of ARG profile of diarrheal samples with varying etiologic agent revealing the presence of ARGs against the most important classes of antibiotics in the gut of diarrheal patients by common, robust molecular methods, which are easily accessible by molecular epidemiological laboratories worldwide.

Mobile Genetic Elements of Vibrio cholerae and the Evolution of Its Antimicrobial Resistance

“…Another study conducted using 1200 VC O1 isolates collected from 1995-2019 revealed that sensitivity of VC O1 El Tor strains arose in 2005 (37). Additionally, on comparison of recent reports on the antibiotic sensitivity profile of VC strains (24) with that of strains isolated a decade ago (38) it was found that a stark difference in the overall antimicrobial resistance profile exists. These findings reveal that AMR in VC is a highly dynamic phenomenon and is prone to variation and evolution with time due to different selective pressure of antibiotics (39).…”

“…Although the problem of AMR has been prevalent since the 1970s the crisis has aggravated over the years and is critical at present (15,23). At present, 100% clinical VC isolates are resistant to nalidixic acid and sulfamethoxazole-trimethoprim (24). In clinical and environmental isolates ARGs which have never been detected in VC previously thereby conferring resistance to antibiotics which worked successfully in its treatment earlier have started appearing, like, the bla NDM-1 carbapenemase encoding gene isolated in environmental and clinical strains of VC (25,26).…”

“…Most of the ARGs in VC are acquired from other organisms and are found on MGEs and are intermittently lost and gained (23). The microbiome plays a potential role in the dissemination of ARGs and in shaping the genome and hence the AMR profile of pathogens (24,39). Most of the AMR determinants discovered in VC from time to time have been found to originate in taxonomically related and unrelated organisms (23,28,42).…”

“…Most of the AMR determinants discovered in VC from time to time have been found to originate in taxonomically related and unrelated organisms (23,28,42). The spread of ARGs is facilitated in polymicrobial ecosystems like the gut and environment where the different inhabitants of the ecosystem are exposed to an interactive milieu conducive for genetic exchange of ARGs (24,43). Genetic exchange occurs by horizontal gene transfer (HGT) and the major vehicles of HGT are the MGEs like plasmids, transposons, integrons and SXT constin.…”

“…AMR in VC is determined by traditional phenotypic methods like disk diffusion method on agar plates or by broth micro dilution methods (24). Alternatively, molecular methods like polymerase chain reaction (PCR) have been widely applied for rapid detection of AMR in VC (24).…”