6NKL

2.2 A resolution structure of VapBC-1 from nontypeable Haemophilus influenzae


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.234 
  • R-Value Work: 0.186 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal Structure of VapBC-1 from Nontypeable Haemophilus influenzae and the Effect of PIN Domain Mutations on Survival during Infection.

Molinaro, A.L.Kashipathy, M.M.Lovell, S.Battaile, K.P.Coussens, N.P.Shen, M.Daines, D.A.

(2019) J.Bacteriol. 201: --

  • DOI: 10.1128/JB.00026-19

  • PubMed Abstract: 
  • Toxin-antitoxin (TA) gene pairs have been identified in nearly all bacterial genomes sequenced to date and are thought to facilitate persistence and antibiotic tolerance. TA loci are classified into various types based upon the characteristics of the ...

    Toxin-antitoxin (TA) gene pairs have been identified in nearly all bacterial genomes sequenced to date and are thought to facilitate persistence and antibiotic tolerance. TA loci are classified into various types based upon the characteristics of their antitoxins, with those in type II expressing proteic antitoxins. Many toxins from type II modules are ribonucleases that maintain a PilT N-terminal (PIN) domain containing conserved amino acids considered essential for activity. The vapBC ( v irulence- a ssociated p rotein) TA system is the largest subfamily in this class and has been linked to pathogenesis of nontypeable Haemophilus influenzae (NTHi). In this study, the crystal structure of the VapBC-1 complex from NTHi was determined to 2.20 Å resolution. Based on this structure, aspartate-to-asparagine and glutamate-to-glutamine mutations of four conserved residues in the PIN domain of the VapC-1 toxin were constructed and the effects of the mutations on protein-protein interactions, growth of Escherichia coli , and pathogenesis ex vivo were tested. Finally, a novel model system was designed and utilized that consists of an NTHi Δ vapBC-1 strain complemented in cis with the TA module containing a mutated or wild-type toxin at an ectopic site on the chromosome. This enabled the analysis of the effect of PIN domain toxin mutants in tandem with their wild-type antitoxin under the control of the vapBC-1 native promoter and in single copy. This is the first report of a system facilitating the study of TA mutant operons in the background of NTHi during infections of primary human tissues ex vivo IMPORTANCE Herein the crystal structure of the VapBC-1 complex from nontypeable Haemophilus influenzae (NTHi) is described. Our results show that some of the mutations in the PIN domain of the VapC-1 toxin were associated with decreased toxicity in E. coli , but the mutants retained the ability to homodimerize and to heterodimerize with the wild-type cognate antitoxin, VapB-1. A new system was designed and constructed to quantify the effects of these mutations on NTHi survival during infections of primary human tissues ex vivo Any mutation to a conserved amino acid in the PIN domain significantly decreased the number of survivors compared to that of the in cis wild-type toxin under the same conditions.


    Organizational Affiliation

    Office of the Dean, College of Sciences, Old Dominion University, Norfolk, Virginia, USA ddaines@odu.edu.,Office of the Dean, College of Sciences, Old Dominion University, Norfolk, Virginia, USA.,Division of Pre-Clinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, USA.,Protein Structure Laboratory, Del Shankel Structural Biology Center, University of Kansas, Lawrence, Kansas, USA.,IMCA-CAT, Hauptman Woodward Medical Research Institute, Argonne, Illinois, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Ribonuclease VapC
A, B
143Haemophilus influenzae (strain ATCC 51907 / DSM 11121 / KW20 / Rd)Mutation(s): 0 
Gene Names: vapC1
EC: 3.1.-.-
Find proteins for Q57122 (Haemophilus influenzae (strain ATCC 51907 / DSM 11121 / KW20 / Rd))
Go to UniProtKB:  Q57122
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Antitoxin VapB1
C, D
96Haemophilus influenzae (strain ATCC 51907 / DSM 11121 / KW20 / Rd)Mutation(s): 0 
Gene Names: vapB1
Find proteins for Q57534 (Haemophilus influenzae (strain ATCC 51907 / DSM 11121 / KW20 / Rd))
Go to UniProtKB:  Q57534
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.234 
  • R-Value Work: 0.186 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 43.880α = 90.00
b = 57.325β = 90.00
c = 175.745γ = 90.00
Software Package:
Software NamePurpose
PDB_EXTRACTdata extraction
XDSdata reduction
Aimlessdata scaling
PHENIXrefinement
PHASERphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute on Deafness and Other Communication Disorders (NIH/NIDCD)United StatesU01 DC014756
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)United StatesP30 GM110761

Revision History 

  • Version 1.0: 2019-04-10
    Type: Initial release
  • Version 1.1: 2019-06-05
    Type: Data collection, Database references
  • Version 1.2: 2019-12-18
    Type: Author supporting evidence