Crystal structure of FemX

Experimental Data Snapshot

  • Resolution: 1.62 Å
  • R-Value Free: 0.237 
  • R-Value Work: 0.221 
  • R-Value Observed: 0.222 

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Structure-based modeling and dynamics of MurM, a Streptococcus pneumoniae penicillin resistance determinant present at the cytoplasmic membrane.

York, A.Lloyd, A.J.Del Genio, C.I.Shearer, J.Hinxman, K.J.Fritz, K.Fulop, V.Dowson, C.G.Khalid, S.Roper, D.I.

(2021) Structure 29: 731-742.e6

  • DOI: https://doi.org/10.1016/j.str.2021.03.001
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    Branched Lipid II, required for the formation of indirectly crosslinked peptidoglycan, is generated by MurM, a protein essential for high-level penicillin resistance in the human pathogen Streptococcus pneumoniae. We have solved the X-ray crystal structure of Staphylococcus aureus FemX, an isofunctional homolog, and have used this as a template to generate a MurM homology model. Using this model, we perform molecular docking and molecular dynamics to examine the interaction of MurM with the phospholipid bilayer and the membrane-embedded Lipid II substrate. Our model suggests that MurM is associated with the major membrane phospholipid cardiolipin, and experimental evidence confirms that the activity of MurM is enhanced by this phospholipid and inhibited by its direct precursor phosphatidylglycerol. The spatial association of pneumococcal membrane phospholipids and their impact on MurM activity may therefore be critical to the final architecture of peptidoglycan and the expression of clinically relevant penicillin resistance in this pathogen.

  • Organizational Affiliation

    School of Life Science, University of Warwick, Coventry, West Midlands CV4 7AL, UK.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Lipid II:glycine glycyltransferase420Staphylococcus aureusMutation(s): 0 
Gene Names: femXfmhB
Find proteins for P0C1Q0 (Staphylococcus aureus)
Explore P0C1Q0 
Go to UniProtKB:  P0C1Q0
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP0C1Q0
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 1.62 Å
  • R-Value Free: 0.237 
  • R-Value Work: 0.221 
  • R-Value Observed: 0.222 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 45.01α = 90
b = 83.62β = 90
c = 133.93γ = 90
Software Package:
Software NamePurpose
XDSdata reduction
XDSdata scaling

Structure Validation

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Entry History & Funding Information

Deposition Data

Funding OrganizationLocationGrant Number
Medical Research Council (United Kingdom)United KingdomMR/M017893/1
Medical Research Council (United Kingdom)United KingdomMR/N002679/1
Biotechnology and Biological Sciences Research CouncilUnited KingdomStudentship

Revision History  (Full details and data files)

  • Version 1.0: 2020-09-09
    Type: Initial release
  • Version 1.1: 2022-03-23
    Changes: Database references
  • Version 1.2: 2024-06-19
    Changes: Data collection