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Class D ?-lactamases do exist in Gram-positive bacteria.

ABSTRACT: Production of ?-lactamases of one of four molecular classes (A, B, C and D) is the major mechanism of bacterial resistance to ?-lactams, the largest class of antibiotics, which have saved countless lives since their inception 70 years ago. Although several hundred efficient class D enzymes have been identified in Gram-negative pathogens over the last four decades, none have been reported in Gram-positive bacteria. Here we demonstrate that efficient class D ?-lactamases capable of hydrolyzing a wide array of ?-lactam substrates are widely disseminated in various species of environmental Gram-positive organisms. Class D enzymes of Gram-positive bacteria have a distinct structural architecture and employ a unique substrate-binding mode that is quite different from that of all currently known class A, C and D ?-lactamases. These enzymes thus constitute a previously unknown reservoir of novel antibiotic-resistance enzymes.

SUBMITTER: Toth M

PROVIDER: S-EPMC4684797 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Class D β-lactamases do exist in Gram-positive bacteria.

Toth Marta M Antunes Nuno Tiago NT Stewart Nichole K NK Frase Hilary H Bhattacharya Monolekha M Smith Clyde A CA Vakulenko Sergei B SB

Nature chemical biology 20151109 1

Production of β-lactamases of one of four molecular classes (A, B, C and D) is the major mechanism of bacterial resistance to β-lactams, the largest class of antibiotics, which have saved countless lives since their inception 70 years ago. Although several hundred efficient class D enzymes have been identified in Gram-negative pathogens over the last four decades, none have been reported in Gram-positive bacteria. Here we demonstrate that efficient class D β-lactamases capable of hydrolyzing a w ...[more]

PMID: 26551395

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