A distinctive role for the Yersinia protein kinase: Actin binding, kinase activation, and cytoskeleton disruption

Stephen J. Juris, Amy E. Rudolph, Don Huddler, Kim Orth, Jack E. Dixon

Research output: Contribution to journalArticle

139 Scopus citations


The bacterial pathogens of the genus Yersinia deliver several virulence factors into target cells using a type III secretion system. We demonstrate that Yersinia protein kinase A (YpkA), an essential bacterial virulence factor, is produced as an inactive serine/threonine kinase. The inactive kinase is activated within the host cell by a cytosolic eukaryotic activator. Using biochemical purification techniques, we demonstrate that actin is a cellular activator of YpkA. This stimulation of YpkA kinase activity by actin depends on the presence of the C-terminal twenty amino acids of YpkA, because deletion of these 20 aa not only obliterates YpkA activity, but it also destroys the interaction between YpkA and actin. Activated YpkA functions within cultured epithelial cells to disrupt the actin cytoskeleton. The disruption of the actin cytoskeleton by YpkA would be expected to inhibit macrophage function and phagocytosis of Yersinia.

Original languageEnglish (US)
Pages (from-to)9431-9436
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Issue number17
Publication statusPublished - Aug 15 2000

ASJC Scopus subject areas

  • Genetics
  • General

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