4WCM

Crystal Structure of Cell Shape Determinant protein Csd4 Gln46His variant from Helicobacter pylori

4WCM の概要

• エントリーDOI: 10.2210/pdb4wcm/pdb
• 関連するPDBエントリー: 4wck 4wcl 4wcn
• 分子名称: Conserved hypothetical secreted protein, IODIDE ION, ZINC ION, ... (6 entities in total)
• 機能のキーワード: mixed alpha beta sandwich, carboxypeptidase, m14, hydrolase
• 由来する生物種: Helicobacter pylori
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 55430.88

構造登録者

Chan, A.C.,Murphy, M.E. (登録日: 2014-09-05, 公開日: 2014-12-24, 最終更新日: 2023-11-15)

主引用文献

Chan, A.C.,Blair, K.M.,Liu, Y.,Frirdich, E.,Gaynor, E.C.,Tanner, M.E.,Salama, N.R.,Murphy, M.E.
Helical Shape of Helicobacter pylori Requires an Atypical Glutamine as a Zinc Ligand in the Carboxypeptidase Csd4.
J.Biol.Chem., 290:3622-3638, 2015

PubMed Abstract: Peptidoglycan modifying carboxypeptidases (CPs) are important determinants of bacterial cell shape. Here, we report crystal structures of Csd4, a three-domain protein from the human gastric pathogen Helicobacter pylori. The catalytic zinc in Csd4 is coordinated by a rare His-Glu-Gln configuration that is conserved among most Csd4 homologs, which form a distinct subfamily of CPs. Substitution of the glutamine to histidine, the residue found in prototypical zinc carboxypeptidases, resulted in decreased enzyme activity and inhibition by phosphate. Expression of the histidine variant at the native locus in a H. pylori csd4 deletion strain did not restore the wild-type helical morphology. Biochemical assays show that Csd4 can cleave a tripeptide peptidoglycan substrate analog to release m-DAP. Structures of Csd4 with this substrate analog or product bound at the active site reveal determinants of peptidoglycan specificity and the mechanism to cleave an isopeptide bond to release m-DAP. Our data suggest that Csd4 is the archetype of a new CP subfamily with a domain scheme that differs from this large family of peptide-cleaving enzymes.

PubMed: 25505267
DOI: 10.1074/jbc.M114.624734

実験手法

X-RAY DIFFRACTION (1.75 Å)