5TEU

Brucella periplasmic binding protein YehZ


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.62 Å
  • R-Value Free: 0.185 
  • R-Value Work: 0.159 
  • R-Value Observed: 0.160 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Conserved ABC Transport System Regulated by the General Stress Response Pathways of Alpha- and Gammaproteobacteria.

Herrou, J.Willett, J.W.Czyz, D.M.Babnigg, G.Kim, Y.Crosson, S.

(2017) J Bacteriol 199

  • DOI: 10.1128/JB.00746-16
  • Primary Citation of Related Structures:  
    5TEU

  • PubMed Abstract: 
  • Brucella abortus σ E1 is an EcfG family sigma factor that regulates the transcription of dozens of genes in response to diverse stress conditions and is required for maintenance of chronic infection in a mouse model. A putative A ...

    Brucella abortus σ E1 is an EcfG family sigma factor that regulates the transcription of dozens of genes in response to diverse stress conditions and is required for maintenance of chronic infection in a mouse model. A putative ATP-binding cassette transporter operon, bab1_0223-bab1_0226 , is among the most highly activated gene sets in the σ E1 regulon. The proteins encoded by the operon resemble quaternary ammonium-compatible solute importers but are most similar in sequence to the broadly conserved YehZYXW system, which remains largely uncharacterized. Transcription of yehZYXW is activated by the general stress sigma factor σ S in Enterobacteriaceae , which suggests a functional role for this transport system in bacterial stress response across the classes Alphaproteobacteria and Gammaproteobacteria We present evidence that B. abortus YehZYXW does not function as an importer of known compatible solutes under physiological conditions and does not contribute to the virulence defect of a σ E1 -null strain. The sole in vitro phenotype associated with genetic disruption of this putative transport system is reduced growth in the presence of high Li + ion concentrations. A crystal structure of B. abortus YehZ revealed a class II periplasmic binding protein fold with significant structural homology to Archaeoglobus fulgidus ProX, which binds glycine betaine. However, the structure of the YehZ ligand-binding pocket is incompatible with high-affinity binding to glycine betaine. This is consistent with weak measured binding of YehZ to glycine betaine and related compatible solutes. We conclude that YehZYXW is a conserved, stress-regulated transport system that is phylogenetically and functionally distinct from quaternary ammonium-compatible solute importers. IMPORTANCE Brucella abortus σ E1 regulates transcription in response to stressors encountered in its mammalian host and is necessary for maintenance of chronic infection in a mouse model. The functions of the majority of genes regulated by σ E1 remain undefined. We present a functional/structural analysis of a conserved putative membrane transport system (YehZYXW) whose expression is strongly activated by σ E1 Though annotated as a quaternary ammonium osmolyte uptake system, experimental physiological studies and measured ligand-binding properties of the periplasmic binding protein (PBP), YehZ, are inconsistent with this function. A crystal structure of B. abortus YehZ provides molecular insight into differences between bona fide quaternary ammonium osmolyte importers and YehZ-related proteins, which form a distinct phylogenetic and functional group of PBPs.


    Organizational Affiliation

    Department of Microbiology, University of Chicago, Chicago, Illinois, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Substrate-binding region of ABC-type glycine betaine transport systemAB301Brucella abortus 2308Mutation(s): 0 
Gene Names: BAB1_0226
Find proteins for Q2YP76 (Brucella abortus (strain 2308))
Explore Q2YP76 
Go to UniProtKB:  Q2YP76
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.62 Å
  • R-Value Free: 0.185 
  • R-Value Work: 0.159 
  • R-Value Observed: 0.160 
  • Space Group: P 42 21 2
  • Diffraction Data DOI: 10.15785/SBGRID/364 SBGrid
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 111.37α = 90
b = 111.37β = 90
c = 122γ = 90
Software Package:
Software NamePurpose
PHENIXrefinement
PHENIXmodel building
PHENIXphasing
xia2data reduction
xia2data scaling

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)United StatesU19AI107792
National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)United StatesR01AI107159

Revision History 

  • Version 1.0: 2017-01-11
    Type: Initial release
  • Version 1.1: 2017-03-01
    Changes: Database references
  • Version 1.2: 2017-09-27
    Changes: Author supporting evidence
  • Version 1.3: 2019-12-11
    Changes: Author supporting evidence