4IMH image
Deposition Date 2013-01-02
Release Date 2013-09-18
Last Version Date 2023-09-20
Entry Detail
PDB ID:
4IMH
Title:
Crystal Structure of Cytoplasmic Heme Binding Protein, PhuS, from Pseudomonas aeruginosa
Biological Source:
Source Organism:
Host Organism:
Method Details:
Experimental Method:
Resolution:
1.98 Å
R-Value Free:
0.22
R-Value Work:
0.17
R-Value Observed:
0.17
Space Group:
I 4
Macromolecular Entities
Polymer Type:polypeptide(L)
Molecule:Hemin degrading factor
Gene (Uniprot):phuS
Chain IDs:A, B
Chain Length:360
Number of Molecules:2
Biological Source:Pseudomonas aeruginosa
Primary Citation
Crystal structure of the Pseudomonas aeruginosa cytoplasmic heme binding protein, Apo-PhuS.
J.Inorg.Biochem. 128C 131 136 (2013)
PMID: 23973453 DOI: 10.1016/j.jinorgbio.2013.07.030

Abstact

Iron is an essential element to all living organisms and is an important determinant of bacterial virulence. Bacteria have evolved specialized systems to sequester and transport iron from the environment or host. Pseudomonas aeruginosa, an opportunistic pathogen, uses two outer membrane receptor mediated systems (Phu and Has) to utilize host heme as a source of iron. PhuS is a 39 kDa soluble cytoplasmic heme binding protein which interacts and transports heme from the inner membrane heme transporter to the cytoplasm where it is degraded by heme oxygenase thus releasing iron. PhuS is unique among other cytoplasmic heme transporter proteins owing to the presence of three histidines in the heme binding pocket which can potentially serve as heme ligands. Out of the three histidine residues on the heme binding helix, His 209 is conserved among heme trafficking proteins while His 210 and His 212 are unique to PhuS. Here we report the crystal structure of PhuS at 1.98Å resolution which shows a unique heme binding pocket and oligomeric structure compared to other known cytoplasmic heme transporter and accounts for some of the unusual biochemical properties of PhuS.

Legend

Protein

Chemical

Disease

Primary Citation of related structures