7A5U

Structure of E37A BlaC from Mycobacterium tuberculosis


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.50 Å
  • R-Value Free: 0.176 
  • R-Value Work: 0.125 
  • R-Value Observed: 0.127 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Conserved residues Glu37 and Trp229 play an essential role in protein folding of beta-lactamase.

Chikunova, A.Manley, M.P.Ud Din Ahmad, M.Bilman, T.Perrakis, A.Ubbink, M.

(2021) FEBS J 288: 5708-5722

  • DOI: https://doi.org/10.1111/febs.15854
  • Primary Citation of Related Structures:  
    7A5U

  • PubMed Abstract: 

    Evolutionary robustness requires that the number of highly conserved amino acid residues in proteins is minimized. In enzymes, such conservation is observed for catalytic residues but also for some residues in the second shell or even further from the active site. β-Lactamases evolve in response to changing antibiotic selection pressures and are thus expected to be evolutionarily robust, with a limited number of highly conserved amino acid residues. As part of the effort to understand the roles of conserved residues in class A β-lactamases, we investigate the reasons leading to the conservation of two amino acid residues in the β-lactamase BlaC, Glu37, and Trp229. Using site-directed mutagenesis, we have generated point mutations of these residues and observed a drastic decrease in the levels of soluble protein produced in Escherichia coli, thus abolishing completely the resistance of bacteria against β-lactam antibiotics. However, the purified proteins are structurally and kinetically very similar to the wild-type enzyme, only differing by exhibiting a slightly lower melting temperature. We conclude that conservation of Glu37 and Trp229 is solely caused by an essential role in the folding process, and we propose that during folding Glu37 primes the formation of the central β-sheet and Trp229 contributes to the hydrophobic collapse into a molten globule. ENZYME: EC 3.5.2.6. DATABASE: Structural data are available in PDB database under the accession number 7A5U.


  • Organizational Affiliation

    Leiden Institute of Chemistry, Leiden University, the Netherlands.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Beta-lactamase274Mycobacterium tuberculosisMutation(s): 1 
Gene Names: blaCERS027646_02769
EC: 3.5.2.6
UniProt
Find proteins for P9WKD3 (Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv))
Explore P9WKD3 
Go to UniProtKB:  P9WKD3
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP9WKD3
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Modified Residues  1 Unique
IDChains TypeFormula2D DiagramParent
OCS
Query on OCS
A
L-PEPTIDE LINKINGC3 H7 N O5 SCYS
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.50 Å
  • R-Value Free: 0.176 
  • R-Value Work: 0.125 
  • R-Value Observed: 0.127 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 38.56α = 90
b = 54.739β = 95
c = 54.509γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
XDSdata reduction
Aimlessdata scaling
MOLREPphasing

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Netherlands Organisation for Scientific Research (NWO)NetherlandsECHO-711.016.002
H2020 Marie Curie Actions of the European CommissionNetherlands653706

Revision History  (Full details and data files)

  • Version 1.0: 2021-04-14
    Type: Initial release
  • Version 1.1: 2021-10-13
    Changes: Data collection, Database references
  • Version 1.2: 2024-01-31
    Changes: Data collection, Refinement description