2w3y

Publication Abstract from PubMed

Erwinia carotovora are phytopathogenic Gram-negative bacteria of agronomic interest as these bacteria are responsible for fruit soft rot and use insects as dissemination vectors. The E. carotovora carotovora strain 15 (Ecc15) is capable of persisting in the Drosophila gut by the sole action of one protein: Erwinia virulence factor (Evf). However, the precise function of Evf is elusive and its sequence does not provide any indications as to its biochemical function. We have solved the 2.0A crystal structure of Evf and found a protein with a complex topology and a novel fold. The structure of Evf confirms that Evf is unlike any virulence factors known to date. Most remarkably, we identified palmitoic acid covalently bound to the totally conserved Cys209 which provides important clues as to the function of Evf. Mutation of the palmitoic binding cysteine leads to a loss of virulence, proving that palmitoylation is at the heart of Evf infectivity and may be a membrane anchoring signal. Fluorescence studies of the sole tryptophan residue (Trp94) demonstrated that Evf was indeed able to bind to model membranes containing negatively charged phospholipids and to promote their aggregation.

Evf, a virulence factor produced by the Drosophila pathogen Erwinia carotovora is a S-palmitoylated protein with a new fold that binds to lipid vesicles.,Quevillon-Cheruel S, Leulliot N, Acosta Muniz C, Vincent M, Gallay J, Argentini M, Cornu D, Boccard F, Lemaitre B, van Tilbeurgh H J Biol Chem. 2008 Nov 1. PMID:18978353^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.