3ZYX

Crystal structure of human monoamine oxidase B in complex with methylene blue and bearing the double mutation I199A-Y326A


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.244 
  • R-Value Work: 0.190 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

The 'Gating' Residues Ile199 and Tyr326 in Human Monoamine Oxidase B Function in Substrate and Inhibitor Recognition.

Milczek, E.M.Binda, C.Rovida, S.Mattevi, A.Edmondson, D.E.

(2011) FEBS J. 278: 4860

  • DOI: 10.1111/j.1742-4658.2011.08386.x

  • PubMed Abstract: 
  • The major structural difference between human monoamine oxidases A (MAO A) and B (MAO B) is that MAO A has a monopartite substrate cavity of ~550 Å(3) volume and MAO B contains a dipartite cavity structure with volumes of ~290 Å(3) (entrance cavity) ...

    The major structural difference between human monoamine oxidases A (MAO A) and B (MAO B) is that MAO A has a monopartite substrate cavity of ~550 Å(3) volume and MAO B contains a dipartite cavity structure with volumes of ~290 Å(3) (entrance cavity) and ~400 Å(3) (substrate cavity). Ile199 and Tyr326 side chains separate these two cavities in MAO B. To probe the function of these gating residues, Ile199Ala and Ile199Ala-Tyr326Ala mutant forms of MAO B were investigated. Structural data on the Ile199Ala MAO B mutant show no alterations in active site geometries compared with wild-type enzyme while the Ile199Ala-Tyr326Ala MAO B mutant exhibits alterations in residues 100-103 which are part of the loop gating the entrance to the active site. Both mutant enzymes exhibit catalytic properties with increased amine K(M) but unaltered k(cat) values. The altered K(M) values on mutation are attributed to the influence of the cavity structure in the binding and subsequent deprotonation of the amine substrate. Both mutant enzymes exhibit weaker binding affinities relative to wild-type enzyme for small reversible inhibitors. Ile199Ala MAO B exhibits an increase in binding affinity for reversible MAO B specific inhibitors which bridge both cavities. The Ile199Ala-Tyr326Ala double mutant exhibits inhibitor binding properties more similar to those of MAO A than to MAO B. These results demonstrate that the bipartite cavity structure in MAO B plays an important role in substrate and inhibitor recognition to distinguish its specificities from those of MAO A and provide insights into specific reversible inhibitor design for these membrane-bound enzymes.


    Organizational Affiliation

    Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
AMINE OXIDASE [FLAVIN-CONTAINING] B
A, B
519Homo sapiensMutation(s): 2 
Gene Names: MAOB
EC: 1.4.3.4
Find proteins for P27338 (Homo sapiens)
Go to Gene View: MAOB
Go to UniProtKB:  P27338
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
FAD
Query on FAD

Download SDF File 
Download CCD File 
A, B
FLAVIN-ADENINE DINUCLEOTIDE
C27 H33 N9 O15 P2
VWWQXMAJTJZDQX-UYBVJOGSSA-N
 Ligand Interaction
MBT
Query on MBT

Download SDF File 
Download CCD File 
A, B
3,7-BIS(DIMETHYLAMINO)PHENOTHIAZIN-5-IUM
METHYLENE BLUE
C16 H18 N3 S
RBTBFTRPCNLSDE-UHFFFAOYSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
MBTKi: 143 nM BINDINGMOAD
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.244 
  • R-Value Work: 0.190 
  • Space Group: C 2 2 2
Unit Cell:
Length (Å)Angle (°)
a = 131.900α = 90.00
b = 224.960β = 90.00
c = 86.630γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
MOSFLMdata reduction
SCALAdata scaling
MOLREPphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-12-14
    Type: Initial release
  • Version 1.1: 2015-04-01
    Type: Data collection