Alliance of Efflux Pumps with β-Lactamases in Multidrug-Resistant Isolates.

Maurya, Navdezda and Jangra, Manoj and Tambat, Rushikesh and Nandanwar, Hemraj (2019) Alliance of Efflux Pumps with β-Lactamases in Multidrug-Resistant Isolates. Microbial drug resistance (Larchmont, N.Y.), 25 (8). pp. 1155-1163. ISSN 1931-8448

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Nosocomial infections caused by are primarily characterized by a high prevalence of extended-spectrum β-lactamases (ESBL's) and a soaring pace of carbapenemase dissemination. Availability of limited antimicrobial agents as a therapeutic option for multidrug-resistant bacteria raises an alarming concern. This study aimed at the molecular characterization of multidrug-resistant clinical isolates and studied the role of efflux pumps in β-lactam resistance. Thirty-three isolates confirmed as ESBL-positive that harbored resistance genes to major classes of antibiotics. The results showed that CTX-M15 was the preeminent β-lactamase along with carbapenemases in ESBL-positive isolates. However, the efficacy of different antibiotics varied in the presence of lactamase inhibitors and efflux pump inhibitors (EPIs). Those showing increased efficacy of antibiotics with EPI were further explored for the expression of efflux pump genes and expressed a significantly different level of efflux pumps. We found that an isolate had higher expression of (SMR family) and (MATE family) pump genes relative to RND family pump genes. No mutations were observed in the genes for porins. Together, the findings suggest that β-lactamases are not the only single factor responsible for providing resistance against the existing β-lactam drugs. Resistance may increase many folds by simultaneous expression of RND family (the most prominent family in Gram-negative bacteria) and other efflux pump family.

Item Type: Article
Additional Information: Copyright of this article belongs to Mary Ann Liebert
Uncontrolled Keywords: Klebsiella pneumoniae; efflux pumps; extended spectrum β-lactamases; multidrug resistance
Subjects: Q Science > QR Microbiology
Depositing User: Dr. K.P.S.Sengar
Date Deposited: 05 Dec 2019 14:31
Last Modified: 05 Dec 2019 14:31

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