Bifunctional quorum-quenching and antibiotic-acylase MacQ forms a 170-kDa capsule-shaped molecule containing spacer polypeptides.

ABSTRACT: Understanding the molecular mechanisms of bacterial antibiotic resistance will help prepare against further emergence of multi-drug resistant strains. MacQ is an enzyme responsible for the multi-drug resistance of Acidovorax sp. strain MR-S7. MacQ has acylase activity against both N-acylhomoserine lactones (AHLs), a class of signalling compounds involved in quorum sensing, and β-lactam antibiotics. Thus, MacQ is crucial as a quencher of quorum sensing as well as in conferring antibiotic resistance in Acidovorax. Here, we report the X-ray structures of MacQ in ligand-free and reaction product complexes. MacQ forms a 170-kDa capsule-shaped molecule via face-to-face interaction with two heterodimers consisting of an α-chain and a β-chain, generated by the self-cleaving activity of a precursor

SUBMITTER: Yasutake Y 

PROVIDER: S-EPMC5566955 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature