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High-affinity binding of phosphatidylinositol 4-phosphate by Legionella pneumophila DrrA.

ABSTRACT: The DrrA protein of Legionella pneumophila is involved in mistargeting of endoplasmic reticulum-derived vesicles to Legionella-containing vacuoles through recruitment of the small GTPase Rab1. To this effect, DrrA binds specifically to phosphatidylinositol 4-phosphate (PtdIns(4)P) lipids on the cytosolic surface of the phagosomal membrane shortly after infection. In this study, we present the atomic structure of the PtdIns(4)P-binding domain of a protein (DrrA) from a human pathogen. A detailed kinetic investigation of its interaction with PtdIns(4)P reveals that DrrA binds to this phospholipid with, as yet unprecedented, high affinity, suggesting that DrrA can sense a very low abundance of the lipid.

SUBMITTER: Schoebel S

PROVIDER: S-EPMC2920447 | biostudies-literature | 2010 Aug

REPOSITORIES: biostudies-literature

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High-affinity binding of phosphatidylinositol 4-phosphate by Legionella pneumophila DrrA.

Schoebel Stefan S Blankenfeldt Wulf W Goody Roger S RS Itzen Aymelt A

EMBO reports 20100709 8

The DrrA protein of Legionella pneumophila is involved in mistargeting of endoplasmic reticulum-derived vesicles to Legionella-containing vacuoles through recruitment of the small GTPase Rab1. To this effect, DrrA binds specifically to phosphatidylinositol 4-phosphate (PtdIns(4)P) lipids on the cytosolic surface of the phagosomal membrane shortly after infection. In this study, we present the atomic structure of the PtdIns(4)P-binding domain of a protein (DrrA) from a human pathogen. A detailed ...[more]

PMID: 20616805

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