3OZB

Crystal Structure of 5'-methylthioinosine phosphorylase from Psedomonas aeruginosa in complex with hypoxanthine


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.262 
  • R-Value Work: 0.202 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Methylthioinosine phosphorylase from Pseudomonas aeruginosa. Structure and annotation of a novel enzyme in quorum sensing.

Guan, R.Ho, M.C.Almo, S.C.Schramm, V.L.

(2011) Biochemistry 50: 1247-1254

  • DOI: 10.1021/bi101642d

  • PubMed Abstract: 
  • The PA3004 gene of Pseudomonas aeruginosa PAO1 was originally annotated as a 5'-methylthioadenosine phosphorylase (MTAP). However, the PA3004 encoded protein uses 5'-methylthioinosine (MTI) as a preferred substrate and represents the only known examp ...

    The PA3004 gene of Pseudomonas aeruginosa PAO1 was originally annotated as a 5'-methylthioadenosine phosphorylase (MTAP). However, the PA3004 encoded protein uses 5'-methylthioinosine (MTI) as a preferred substrate and represents the only known example of a specific MTI phosphorylase (MTIP). MTIP does not utilize 5'-methylthioadenosine (MTA). Inosine is a weak substrate with a k(cat)/K(m) value 290-fold less than MTI and is the second best substrate identified. The crystal structure of P. aeruginosa MTIP (PaMTIP) in complex with hypoxanthine was determined to 2.8 Å resolution and revealed a 3-fold symmetric homotrimer. The methylthioribose and phosphate binding regions of PaMTIP are similar to MTAPs, and the purine binding region is similar to that of purine nucleoside phosphorylases (PNPs). The catabolism of MTA in P. aeruginosa involves deamination to MTI and phosphorolysis to hypoxanthine (MTA → MTI → hypoxanthine). This pathway also exists in Plasmodium falciparum, where the purine nucleoside phosphorylase (PfPNP) acts on both inosine and MTI. Three tight-binding transition state analogue inhibitors of PaMTIP are identified with dissociation constants in the picomolar range. Inhibitor specificity suggests an early dissociative transition state for PaMTIP. Quorum sensing molecules are associated with MTA metabolism in bacterial pathogens suggesting PaMTIP as a potential therapeutic target.


    Organizational Affiliation

    Department of Biochemistry, Albert Einstein College of Medicine, Yeshiva University, 1300 Morris Park Avenue, Bronx, New York 10461, United States.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Methylthioadenosine phosphorylase
A, B, C, D, E, F
259Pseudomonas aeruginosa (strain ATCC 15692 / DSM 22644 / CIP 104116 / JCM 14847 / LMG 12228 / 1C / PRS 101 / PAO1)Mutation(s): 0 
EC: 2.4.2.44
Find proteins for Q9HZK1 (Pseudomonas aeruginosa (strain ATCC 15692 / DSM 22644 / CIP 104116 / JCM 14847 / LMG 12228 / 1C / PRS 101 / PAO1))
Go to UniProtKB:  Q9HZK1
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download SDF File 
Download CCD File 
A, B, C
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
HPA
Query on HPA

Download SDF File 
Download CCD File 
A, B, C, D, E, F
HYPOXANTHINE
C5 H4 N4 O
FDGQSTZJBFJUBT-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.262 
  • R-Value Work: 0.202 
  • Space Group: P 41 21 2
Unit Cell:
Length (Å)Angle (°)
a = 99.469α = 90.00
b = 99.469β = 90.00
c = 334.935γ = 90.00
Software Package:
Software NamePurpose
MOLREPphasing
PDB_EXTRACTdata extraction
SCALEPACKdata scaling
REFMACrefinement
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-08-10
    Type: Initial release
  • Version 1.1: 2017-11-08
    Type: Refinement description