 |
PDBsum entry 4yf9
|
|
|
|
|
 |
Contents |
 |
|
|
|
|
|
|
|
|
|
|
|
167 a.a.
|
|
|
|
|
|
|
|
|
|
|
15 a.a.
|
|
|
|
|
|
|
|
|
|
|
575 a.a.
|
|
|
|
|
|
|
|
|
|
|
14 a.a.
|
|
|
|
|
|
|
|
|
|
|
16 a.a.
|
|
|
|
|
|
|
|
|
|
|
|
References listed in PDB file
|
|
|
Key reference
|
|
|
Title
|
|
Bifunctional quorum-Quenching and antibiotic-Acylase macq forms a 170-Kda capsule-Shaped molecule containing spacer polypeptides.
|
|
|
Authors
|
|
Y.Yasutake,
H.Kusada,
T.Ebuchi,
S.Hanada,
Y.Kamagata,
T.Tamura,
N.Kimura.
|
|
|
Ref.
|
|
Sci Rep, 2017,
7,
8946.
|
|
|
PubMed id
|
|
|
|
|
|
|
|
|
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 polypeptide. The electron density of the
spacer polypeptide in the hollow of the molecule revealed the close orientation
of the peptide-bond atoms of Val20SP-Gly21SP to the active-site, implying a role
of the residues in substrate binding. In mutational analyses, uncleaved MacQ
retained degradation activity against both AHLs and penicillin G. These results
provide novel insights into the mechanism of self-cleaving maturation and
enzymatic function of N-terminal nucleophile hydrolases.
|
|
|
|
|
|
|
