1BMT

HOW A PROTEIN BINDS B12: A 3.O ANGSTROM X-RAY STRUCTURE OF THE B12-BINDING DOMAINS OF METHIONINE SYNTHASE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3 Å
  • R-Value Work: 0.170 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

How a protein binds B12: A 3.0 A X-ray structure of B12-binding domains of methionine synthase.

Drennan, C.L.Huang, S.Drummond, J.T.Matthews, R.G.Lidwig, M.L.

(1994) Science 266: 1669-1674


  • PubMed Abstract: 
  • The crystal structure of a 27-kilodalton methylcobalamin-containing fragment of methionine synthase from Escherichia coli was determined at 3.0 A resolution. This structure depicts cobalamin-protein interactions and reveals that the corrin macrocycle ...

    The crystal structure of a 27-kilodalton methylcobalamin-containing fragment of methionine synthase from Escherichia coli was determined at 3.0 A resolution. This structure depicts cobalamin-protein interactions and reveals that the corrin macrocycle lies between a helical amino-terminal domain and an alpha/beta carboxyl-terminal domain that is a variant of the Rossmann fold. Methylcobalamin undergoes a conformational change on binding the protein; the dimethylbenzimidazole group, which is coordinated to the cobalt in the free cofactor, moves away from the corrin and is replaced by a histidine contributed by the protein. The sequence Asp-X-His-X-X-Gly, which contains this histidine ligand, is conserved in the adenosylcobalamin-dependent enzymes methylmalonyl-coenzyme A mutase and glutamate mutase, suggesting that displacement of the dimethylbenzimidazole will be a feature common to many cobalamin-binding proteins. Thus the cobalt ligand, His759, and the neighboring residues Asp757 and Ser810, may form a catalytic quartet, Co-His-Asp-Ser, that modulates the reactivity of the B12 prosthetic group in methionine synthase.


    Related Citations: 
    • Cobalamin-Dependent Methionine Synthase: The Structure of a Methylcobalamin-Binding Fragment and Implications for Other B12-Dependent Enzymes
      Drennan, C.L.,Matthews, R.G.,Ludwig, M.L.
      (1994) Curr.Opin.Struct.Biol. 4: 919


    Organizational Affiliation

    Biophysics Research Division, University of Michigan, Ann Arbor 48109-1055.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
METHIONINE SYNTHASE
A, B
246Escherichia coli (strain K12)Gene Names: metH
EC: 2.1.1.13
Find proteins for P13009 (Escherichia coli (strain K12))
Go to UniProtKB:  P13009
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
COB
Query on COB

Download SDF File 
Download CCD File 
A, B
CO-METHYLCOBALAMIN
C63 H91 Co N13 O14 P
BMOGZGJBQIUQJG-BYLSPCLQSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3 Å
  • R-Value Work: 0.170 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 96.700α = 90.00
b = 55.300β = 90.00
c = 103.800γ = 90.00
Software Package:
Software NamePurpose
X-PLORphasing
X-PLORmodel building
X-PLORrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1995-06-03
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance