2IWC

Benzylpenicilloyl-acylated MecR1 extracellular antibiotic-sensor domain.


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.234 
  • R-Value Work: 0.187 
  • R-Value Observed: 0.189 

Starting Model: experimental
View more details

wwPDB Validation   3D Report Full Report


This is version 2.1 of the entry. See complete history


Literature

Unbound and Acylated Structures of the Mecr1 Extracellular Antibiotic-Sensor Domain Provide Insights Into the Signal-Transduction System that Triggers Methicillin Resistance.

Marrero, A.Mallorqui-Fernandez, G.Guevara, T.Garcia-Castellanos, R.Gomis-Ruth, F.X.

(2006) J Mol Biol 361: 506

  • DOI: https://doi.org/10.1016/j.jmb.2006.06.046
  • Primary Citation of Related Structures:  
    2IWB, 2IWC, 2IWD

  • PubMed Abstract: 

    Methicillin-resistant Staphylococcus aureus (MRSA) strains are responsible for most hospital-onset bacterial infections. Lately, they have become a major threat to the community through infections of skin, soft tissue and respiratory tract, and subsequent septicaemia or septic shock. MRSA strains are resistant to most beta-lactam antibiotics (BLAs) as a result of the biosynthesis of a penicillin-binding protein with low affinity for BLAs, called PBP2a, PBP2' or MecA. This response is regulated by the chromosomal mec-divergon, which encodes a signal-transduction system including a transcriptional repressor, MecI, and a sensor/transducer, MecR1, as well as the structural mecA gene. This system is similar to those encoded by bla divergons in S. aureus and Bacillus licheniformis. MecR1 comprises an integral-membrane latent metalloprotease domain facing the cytosol and an extracellular sensor domain. The latter binds BLAs and transmits a signal through the membrane that eventually triggers activation of the metalloprotease moiety, which in turn switches off MecI-induced repression of mecA transcription. The MecR1 sensor domain, MecR1-PBD, reveals a two-domain structure of alpha/beta-type fold reminiscent of penicillin-binding proteins and beta-lactamases, and a catalytic serine residue as the ultimate cause for BLA-binding. Covalent complexes with benzylpenicillin and oxacillin provide evidence that serine acylation does not entail significant structural changes, thus supporting the hypothesis that additional extracellular segments of MecR1 are involved in signal transmission. The chemical nature of the residues shaping the active-site cleft favours stabilisation of the acyl enzyme complexes in MecR1-PBD, in contrast to the closely related OXA beta-lactamases, where the cleft is more likely to promote subsequent hydrolysis. The present structural data provide insights into the mec-encoded BLA-response mechanism and an explanation for kinetic differences in signal transmission with the related bla-encoded systems.


  • Organizational Affiliation

    Institut de Biologia Molecular de Barcelona, C.I.D.-C.S.I.C. C/Jordi Girona, 18-26 08034 Barcelona, Spain.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
METHICILLIN RESISTANCE MECR1 PROTEIN255Staphylococcus aureus subsp. aureus N315Mutation(s): 0 
UniProt
Find proteins for P0A0B0 (Staphylococcus aureus (strain N315))
Explore P0A0B0 
Go to UniProtKB:  P0A0B0
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP0A0B0
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
PNM
Query on PNM

Download Ideal Coordinates CCD File 
B [auth A]OPEN FORM - PENICILLIN G
C16 H20 N2 O4 S
OGFZUTGOGYUTKZ-KWCYVHTRSA-N
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.234 
  • R-Value Work: 0.187 
  • R-Value Observed: 0.189 
  • Space Group: P 41 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 58.4α = 90
b = 58.4β = 90
c = 148.05γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
XDSdata reduction
COMBATdata scaling
SCALAdata scaling
AMoREphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2006-07-04
    Type: Initial release
  • Version 1.1: 2011-05-08
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2018-03-28
    Changes: Source and taxonomy
  • Version 2.0: 2018-10-24
    Changes: Advisory, Atomic model, Data collection, Derived calculations, Non-polymer description, Polymer sequence, Source and taxonomy, Structure summary
  • Version 2.1: 2023-12-13
    Changes: Data collection, Database references, Refinement description