Helicobacter pylori CagA inhibits PAR1-MARK family kinases by mimicking host substrates.
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ABSTRACT:
SUBMITTER: Nesic D
PROVIDER: S-EPMC3006182 | biostudies-literature | 2010 Jan
REPOSITORIES: biostudies-literature
Publications
Helicobacter pylori CagA inhibits PAR1-MARK family kinases by mimicking host substrates.
Nesić Dragana D Miller Marshall C MC Quinkert Zachary T ZT Stein Markus M Chait Brian T BT Stebbins C Erec CE
Nature structural & molecular biology 20091206 1
The CagA protein of Helicobacter pylori interacts with numerous cellular factors and is associated with increased virulence and risk of gastric carcinoma. We present here the cocrystal structure of a subdomain of CagA with the human kinase PAR1b/MARK2, revealing that a CagA peptide mimics substrates of this kinase family, resembling eukaryotic protein kinase inhibitors. Mutagenesis of conserved residues central to this interaction renders CagA inactive as an inhibitor of MARK2. ...[more]
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