1XMF

Structure of Mn(II)-Soaked Apo Methane Monooxygenase Hydroxylase Crystals from M. capsulatus (Bath)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.32 Å
  • R-Value Free: 0.263 
  • R-Value Work: 0.219 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Preparation and X-ray Structures of Metal-Free, Dicobalt and Dimanganese Forms of Soluble Methane Monooxygenase Hydroxylase from Methylococcus capsulatus (Bath)

Sazinsky, M.H.Merkx, M.Cadieux, E.Tang, S.Lippard, S.J.

(2004) Biochemistry 43: 16263-16276

  • DOI: 10.1021/bi048140z
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • A three-component soluble methane monooxygenase (sMMO) enzyme system catalyzes the hydroxylation of methane to methanol at a carboxylate-bridged diiron center housed in the alpha-subunit of the hydroxylase (MMOH). Catalysis is facilitated by the pres ...

    A three-component soluble methane monooxygenase (sMMO) enzyme system catalyzes the hydroxylation of methane to methanol at a carboxylate-bridged diiron center housed in the alpha-subunit of the hydroxylase (MMOH). Catalysis is facilitated by the presence of a regulatory protein (MMOB) and inhibited by MMOD, a protein of unknown function encoded in the sMMO operon. Both MMOB and MMOD are presumed to bind to the same region of the MMOH alpha-subunit. A colorimetric method for monitoring removal of Fe(II) from MMOH was developed using 1,10-phenanthroline and yields apo MMOH with <0.1 Fe/homodimer. With the use of this method, it was possible to investigate the X-ray structure of the apoenzyme and to perform metal reconstitution studies. Using MMOH from Methylococccus capsulatus (Bath), the effects of MMOB and MMOD on metal binding were studied and structural perturbations relevant to the function of this enzyme were identified. X-ray crystal structures of the apo, Mn(II)-soaked, and Co(II)-grown MMOH, determined to 2.3 A or greater resolution, reveal that the presence of metal ions is essential for the proper folding of helices E, F, and H of the alpha-subunit. The active sites of Mn(II)-soaked and Co(II)-grown MMOH are similar to that of reduced, native MMOH with notable differences in the metal-metal distances and ligand coordination sphere that may reflect how this dinuclear metal center might change in the presence of MMOB. MMOB and MMOD decrease the rate of removal of Fe(II) from the enzyme by 22- and 16-fold, respectively. On the basis of previous studies, it is hypothesized that MMOB, and perhaps MMOD, function to block solvent access to the MMOH active site. Finally, ITC studies and the observed disorder in helices E, F, and H in the apo and Mn(II)-soaked structures suggest that these regions of MMOH are critical for MMOB and MMOD binding.


    Organizational Affiliation

    Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Methane monooxygenase component A alpha chain
A, B
527Methylococcus capsulatus (strain ATCC 33009 / NCIMB 11132 / Bath)Mutation(s): 0 
Gene Names: mmoX
EC: 1.14.13.25
Find proteins for P22869 (Methylococcus capsulatus (strain ATCC 33009 / NCIMB 11132 / Bath))
Go to UniProtKB:  P22869
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Methane monooxygenase component A beta chain
C, D
388Methylococcus capsulatus (strain ATCC 33009 / NCIMB 11132 / Bath)Mutation(s): 0 
Gene Names: mmoY
EC: 1.14.13.25
Find proteins for P18798 (Methylococcus capsulatus (strain ATCC 33009 / NCIMB 11132 / Bath))
Go to UniProtKB:  P18798
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
Methane monooxygenase component A gamma chain
E, F
169Methylococcus capsulatus (strain ATCC 33009 / NCIMB 11132 / Bath)Mutation(s): 0 
Gene Names: mmoZ
EC: 1.14.13.25
Find proteins for P11987 (Methylococcus capsulatus (strain ATCC 33009 / NCIMB 11132 / Bath))
Go to UniProtKB:  P11987
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MN
Query on MN

Download SDF File 
Download CCD File 
A, B
MANGANESE (II) ION
Mn
WAEMQWOKJMHJLA-UHFFFAOYSA-N
 Ligand Interaction
CA
Query on CA

Download SDF File 
Download CCD File 
A, C
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.32 Å
  • R-Value Free: 0.263 
  • R-Value Work: 0.219 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 70.820α = 90.00
b = 171.679β = 90.00
c = 220.275γ = 90.00
Software Package:
Software NamePurpose
CNSrefinement
SCALEPACKdata scaling
MAR345data collection
CNSphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2005-01-18
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Source and taxonomy, Version format compliance
  • Version 1.3: 2017-10-11
    Type: Refinement description