Functional metagenomics reveals a novel carbapenem-hydrolyzing mobile beta-lactamase from Indian river sediments contaminated with antibiotic production waste

Sewage effluent from an Indian hospital harbors novel carbapenemases and integron-borne antibiotic resistance genes

“…The betalactam hydrolytic profile of the bla RSA1 protein resembled that of GES-2. Although bla RSA1 does not hydrolyze carbapenems, there is a possibility that natural mutants might occur which may possess this activity, as is the case for other GES variants [13]. The same may apply for other ESBLs, as was recently demonstrated by the discovery of a natural mutant of OXA-10 with increased carbapenemase activity in Swedish hospital effluent [59].…”

“…The recently described novel sulfonamide resistance gene sul4 was detected along with the ISCR20 transposes as described earlier [21]. Both sul4 and bla RSA1 were first described from river sediments contaminated with waste from drug manufacturing plants near Hyderabad, India, and concerns were raised about finding these genes in clinical isolates [13,21]. The presence of these genes in integron gene cassettes from hospital effluent suggests that these genes are accessible to pathogens and might already have made their way into human pathogens.…”

“…With regards to novel MBLs derived from the HMM analyses, seven novel genes from different clades of phylogenetic tree representing subclass B3 were selected for functional verification along with one gene representing subclass B2. The candidate novel genes were synthesized at ThermoFisher Scientific, Germany, using their GeneArt Gene Synthesis service and subcloned into the expression vector pZE21-MCS1 as described previously [13]. The plasmids containing novel resistance gene candidates were then transformed into E. coli C600Z1 (Expressys, Germany) by electroporation.…”

“…Functional metagenomics is another strategy that has the ability to identify novel ARGs without apparent similarities to known ARGs as it is based on a functional selection of DNA fragments expressed in a surrogate host like Escherichia coli [12]. With such an approach, we have identified novel ARGs, including one encoding a carbapenem hydrolyzing beta-lactamase, from river sediments contaminated with drug production waste [13]. Several studies, using functional metagenomics, have reported novel resistance genes from a variety of environments like human gut, soil, and seawater [14][15][16][17][18].…”

Field‐compatible protocol for detecting tetracyclines with bioluminescent bioreporters without pipetting steps

“…Using antibiotics in food production may spread antibiotic contamination to the farm environment and also foodstuffs may contain antibiotic residues . In addition to the contamination as a result of use, also direct discharges from manufacturing of antibiotics have been reported and evidence suggests that these wastewaters contribute to the emergence of antimicrobial resistance . Defining the risks of antibiotic contamination in the environment and in foodstuffs would require rapid screening methods in order to identify the contaminated sites or food products cost‐efficiently.…”