1s28
From Proteopedia
Crystal Structure of AvrPphF ORF1, the Chaperone for the Type III Effector AvrPphF ORF2 from P. syringae
Overview
The avrPphF locus from Pseudomonas syringae pv. phaseolicola, the causative agent of bean halo-blight disease, encodes proteins which either enhance virulence on susceptible hosts or elicit defense responses on hosts carrying the R1 resistance gene. Here we present the crystal structures of the two proteins from the avrPphF operon. The structure of AvrPphF ORF1 is strikingly reminiscent of type III chaperones from bacterial pathogens of animals, indicating structural conservation of these specialized chaperones, despite high sequence divergence. The AvrPphF ORF2 effector adopts a novel "mushroom"-like structure containing "head" and "stalk" subdomains. The head subdomain possesses limited structural homology to the catalytic domain of bacterial ADP-ribosyltransferases (ADP-RTs), though no ADP-RT activity was detected for AvrPphF ORF2 in standard assays. Nonetheless, this structural similarity identified two clusters of conserved surface-exposed residues important for both virulence mediated by AvrPphF ORF2 and recognition of this effector by bean plants expressing the R1 resistance gene.
About this Structure
1S28 is a Single protein structure of sequence from Pseudomonas syringae pv. phaseolicola. Full crystallographic information is available from OCA.
Reference
Crystal structures of the type III effector protein AvrPphF and its chaperone reveal residues required for plant pathogenesis., Singer AU, Desveaux D, Betts L, Chang JH, Nimchuk Z, Grant SR, Dangl JL, Sondek J, Structure. 2004 Sep;12(9):1669-81. PMID:15341731 Page seeded by OCA on Sat May 3 08:12:19 2008