skip to main content

Title: Structure of Rhodococcus equi virulence-associated protein B (VapB) reveals an eight-stranded antiparallel β-barrel consisting of two Greek-key motifs

The structure of VapB, a member of the Vap protein family that is involved in virulence of the bacterial pathogen R. equi, was determined by SAD phasing and reveals an eight-stranded antiparallel β-barrel similar to avidin, suggestive of a binding function. Made up of two Greek-key motifs, the topology of VapB is unusual or even unique. Members of the virulence-associated protein (Vap) family from the pathogen Rhodococcus equi regulate virulence in an unknown manner. They do not share recognizable sequence homology with any protein of known structure. VapB and VapA are normally associated with isolates from pigs and horses, respectively. To contribute to a molecular understanding of Vap function, the crystal structure of a protease-resistant VapB fragment was determined at 1.4 Å resolution. The structure was solved by SAD phasing employing the anomalous signal of one endogenous S atom and two bound Co ions with low occupancy. VapB is an eight-stranded antiparallel β-barrel with a single helix. Structural similarity to avidins suggests a potential binding function. Unlike other eight- or ten-stranded β-barrels found in avidins, bacterial outer membrane proteins, fatty-acid-binding proteins and lysozyme inhibitors, Vaps do not have a next-neighbour arrangement but consist of two Greek-key motifs with strand ordermore » 41238567, suggesting an unusual or even unique topology.« less
Authors:
 [1] ; ;  [2] ;  [1]
  1. Bielefeld University, Universitaetsstrasse 25, 33615 Bielefeld (Germany)
  2. University of Bonn, Ulrich-Haberland Strasse 61a, 53121 Bonn (Germany)
Publication Date:
OSTI Identifier:
22375691
Resource Type:
Journal Article
Resource Relation:
Journal Name: Acta crystallographica. Section F, Structural biology communications; Journal Volume: 70; Journal Issue: Pt 7; Other Information: PMCID: PMC4089522; PMID: 25005079; PUBLISHER-ID: hv5258; OAI: oai:pubmedcentral.nih.gov:4089522; Copyright (c) Geerds et al. 2014; This is an open-access article distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ATOMS; CARBOXYLIC ACIDS; CRYSTAL STRUCTURE; LYSOZYME; POTENTIALS; RESOLUTION; SIGNALS; TOPOLOGY