5BWJ

Structural characterization and modeling of the Borrelia burgdorferi hybrid histidine kinase Hk1 periplasmic sensor


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.05 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.193 
  • R-Value Observed: 0.195 

wwPDB Validation   3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

Structural characterization and modeling of the Borrelia burgdorferi hybrid histidine kinase Hk1 periplasmic sensor: A system for sensing small molecules associated with tick feeding.

Bauer, W.J.Luthra, A.Zhu, G.Radolf, J.D.Malkowski, M.G.Caimano, M.J.

(2015) J Struct Biol 192: 48-58

  • DOI: 10.1016/j.jsb.2015.08.013
  • Primary Citation of Related Structures:  
    5BWJ

  • PubMed Abstract: 
  • Two-component signal transduction systems are the primary mechanisms by which bacteria perceive and respond to changes in their environment. The Hk1/Rrp1 two-component system (TCS) in Borrelia burgdorferi consists of a hybrid histidine kinase and a response regulator with diguanylate cyclase activity, respectively ...

    Two-component signal transduction systems are the primary mechanisms by which bacteria perceive and respond to changes in their environment. The Hk1/Rrp1 two-component system (TCS) in Borrelia burgdorferi consists of a hybrid histidine kinase and a response regulator with diguanylate cyclase activity, respectively. Phosphorylated Rrp1 catalyzes the synthesis of c-di-GMP, a second messenger associated with bacterial life-style control networks. Spirochetes lacking either Hk1 or Rrp1 are virulent in mice but destroyed within feeding ticks. Activation of Hk1 by exogenous stimuli represents the seminal event for c-di-GMP signaling. We reasoned that structural characterization of Hk1's sensor would provide insights into the mechanism underlying signal transduction and aid in the identification of activating ligands. The Hk1 sensor is composed of three ligand-binding domains (D1-3), each with homology to periplasmic solute-binding proteins (PBPs) typically associated with ABC transporters. Herein, we determined the structure for D1, the most N-terminal PBP domain. As expected, D1 displays a bilobed Venus Fly Trap-fold. Similar to the prototypical sensor PBPs HK29S from Geobacter sulfurreducens and VFT2 from Bordetella pertussis, apo-D1 adopts a closed conformation. Using complementary approaches, including SAXS, we established that D1 forms a dimer in solution. The D1 structure enabled us to model the D2 and D3 domains. Differences in the ligand-binding pockets suggest that each PBP recognizes a different ligand. The ability of Hk1 to recognize multiple stimuli provides spirochetes with a means of distinguishing between the acquisition and transmission blood meals and generate a graded output response that is reflective of the perceived environmental threats.


    Organizational Affiliation

    Connecticut Children's Medical Center, Hartford, CT 06106.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Sensory transduction histidine kinase, putativeA, B, C, D227Borreliella burgdorferi B31Mutation(s): 0 
Gene Names: BB_0420
Find proteins for O51381 (Borrelia burgdorferi (strain ATCC 35210 / B31 / CIP 102532 / DSM 4680))
Explore O51381 
Go to UniProtKB:  O51381
Protein Feature View
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.05 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.193 
  • R-Value Observed: 0.195 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 58.3α = 90
b = 62.853β = 101.32
c = 111.808γ = 90
Software Package:
Software NamePurpose
PHENIXrefinement
Cootmodel building
PDB_EXTRACTdata extraction
HKL-2000data scaling
HKL-2000data reduction
PHASERphasing

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 StatesAI 29735
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)United StatesGM 094611

Revision History  (Full details and data files)

  • Version 1.0: 2015-07-29
    Type: Initial release
  • Version 1.1: 2015-09-23
    Changes: Database references
  • Version 1.2: 2015-10-28
    Changes: Database references
  • Version 1.3: 2017-09-20
    Changes: Author supporting evidence, Database references, Derived calculations
  • Version 1.4: 2019-12-11
    Changes: Author supporting evidence