Role of Histidine 269 in Catalysis by Monomeric Sarcosine Oxidase

Experimental Data Snapshot

  • Resolution: 1.95 Å
  • R-Value Free: 0.216 
  • R-Value Work: 0.171 

wwPDB Validation   3D Report Full Report

Ligand Structure Quality Assessment 

This is version 1.5 of the entry. See complete history


Monomeric sarcosine oxidase: role of histidine 269 in catalysis.

Zhao, G.Song, H.Chen, Z.W.Mathews, F.S.Jorns, M.S.

(2002) Biochemistry 41: 9751-9764

  • DOI: https://doi.org/10.1021/bi020286f
  • Primary Citation of Related Structures:  
    1L9C, 1L9D, 1L9E

  • PubMed Abstract: 

    Conservative mutation of His269 (to Asn, Ala, or Gln) does not-significantly affect the expression of monomeric sarcosine oxidase (MSOX), covalent flavinylation, the physicochemical properties of bound FAD, or the overall protein structure. Turnover with sarcosine and the limiting rate of the reductive half-reaction with L-proline at pH 8.0 are, however, nearly 2 orders of magnitude slower than that with with wild-type MSOX. The crystal structure of the His269Asn complex with pyrrole-2-carboxylate shows that the pyrrole ring of the inhibitor is displaced as compared with wild-type MSOX. The His269 mutants all form charge-transfer complexes with pyrrole-2-carboxylate or methylthioacetate, but the charge-transfer bands are shifted to shorter wavelengths (higher energy) as compared with wild-type MSOX. Both wild-type MSOX and the His269Asn mutant bind the zwitterionic form of L-proline. The E(ox).L-proline complex formed with the His269Asn mutant or wild-type MSOX contains an ionizable group (pK(a) = 8.0) that is required for conversion of the zwitterionic L-proline to the reactive anionic form, indicating that His269 is not the active-site base. We propose that the change in ligand orientation observed upon mutation of His269 results in a less than optimal overlap of the highest occupied orbital of the ligand with the lowest unoccupied orbital of the flavin. The postulated effect on orbital overlap may account for the increased energy of charge-transfer bands and the slower rates of electron transfer observed for mutant enzyme complexes with charge-transfer ligands and substrates, respectively.

  • Organizational Affiliation

    Department of Biochemistry, MCP Hahnemann School of Medicine, Philadelphia, PA 19129, USA.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Monomeric sarcosine oxidase
A, B
389Bacillus sp. B-0618Mutation(s): 1 
Find proteins for P40859 (Bacillus sp. (strain B-0618))
Explore P40859 
Go to UniProtKB:  P40859
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP40859
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 1.95 Å
  • R-Value Free: 0.216 
  • R-Value Work: 0.171 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 71.413α = 90
b = 69.771β = 92.22
c = 73.169γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report

Ligand Structure Quality Assessment 

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2002-08-30
    Type: Initial release
  • Version 1.1: 2008-04-28
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Source and taxonomy, Version format compliance
  • Version 1.3: 2017-10-11
    Changes: Refinement description
  • Version 1.4: 2021-10-27
    Changes: Database references, Derived calculations
  • Version 1.5: 2023-08-16
    Changes: Data collection, Refinement description