Dataset Information

The structure of Helicobacter pylori HP0310 reveals an atypical peptidoglycan deacetylase.

ABSTRACT: Peptidoglycan deacetlyase (HP0310, HpPgdA) from the gram-negative pathogen Helicobacter pylori, has been indicated as the enzyme responsible for a peptidoglycan modification that counteracts the host immune response. HpPgdA has been cloned, purified and expressed in good yield in E. coli. It has been crystallized, its structure determined and activity tests in vitro performed. The enzyme, which belongs to the polysaccharide deacetylases protein family, is a homo-tetramer. The four polypeptide chains, each folded into a single domain characterized by a non-canonical TIM-barrel fold, are arranged around a four-fold symmetry axis. The active site, one per monomer, contains a heavy ion coordinated in a way similar to other deacetylases. However, the enzyme showed no in vitro activity on the typical polysaccharide substrates of peptidoglycan deacetylases. In striking contrast with the known peptidoglycan deacetylases, HpPgdA does not exhibit a solvent-accessible polysaccharide binding groove, suggesting that the enzyme binds a small molecule at the active site.

SUBMITTER: Shaik MM

PROVIDER: S-EPMC3084791 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

The structure of Helicobacter pylori HP0310 reveals an atypical peptidoglycan deacetylase.

Shaik Md Munan MM Cendron Laura L Percudani Riccardo R Zanotti Giuseppe G

PloS one 20110429 4

Peptidoglycan deacetlyase (HP0310, HpPgdA) from the gram-negative pathogen Helicobacter pylori, has been indicated as the enzyme responsible for a peptidoglycan modification that counteracts the host immune response. HpPgdA has been cloned, purified and expressed in good yield in E. coli. It has been crystallized, its structure determined and activity tests in vitro performed. The enzyme, which belongs to the polysaccharide deacetylases protein family, is a homo-tetramer. The four polypeptide ch ...[more]

PMID: 21559431

Similar Datasets

Project description:UNLABELLED:Helicobacter pylori chronically infects the gastric mucosa in more than half of the human population; in a subset of this population, its presence is associated with development of severe disease, such as gastric cancer. Genomic analysis of several strains has revealed an extensive H. pylori pan-genome, likely to grow as more genomes are sampled. Here we describe the draft genome sequence (63 contigs; 26× mean coverage) of H. pylori strain B45, isolated from a patient with gastric mucosa-associated lymphoid tissue (MALT) lymphoma. The major finding was a 24.6-kb prophage integrated in the bacterial genome. The prophage shares most of its genes (22/27) with prophage region II of Helicobacter acinonychis strain Sheeba. After UV treatment of liquid cultures, circular DNA carrying the prophage integrase gene could be detected, and intracellular tailed phage-like particles were observed in H. pylori cells by transmission electron microscopy, indicating that phage production can be induced from the prophage. PCR amplification and sequencing of the integrase gene from 341 H. pylori strains from different geographic regions revealed a high prevalence of the prophage (21.4%). Phylogenetic reconstruction showed four distinct clusters in the integrase gene, three of which tended to be specific for geographic regions. Our study implies that phages may play important roles in the ecology and evolution of H. pylori. IMPORTANCE:Helicobacter pylori chronically infects the gastric mucosa in more than half of the human population, and while most of the infected individuals do not develop disease, H. pylori infection doubles the risk of developing gastric cancer. An abundance and diversity of viruses (phages) infect microbial populations in most environments and are important mediators of microbial diversity. Our finding of a 24.6-kb prophage integrated inside an H. pylori genome and the observation of circular integrase gene-containing DNA and phage-like particles inside cells upon UV treatment demonstrate that we have discovered a viable H. pylori phage. The additional finding of integrase genes in a large proportion of screened isolates of diverse geographic origins indicates that the prevalence of prophages may have been underestimated in H. pylori. Since phages are important drivers of microbial evolution, the discovery should be important for understanding and predicting genetic diversity in H. pylori.

Dataset Information

The structure of Helicobacter pylori HP0310 reveals an atypical peptidoglycan deacetylase.

Publications

The structure of Helicobacter pylori HP0310 reveals an atypical peptidoglycan deacetylase.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets