1U9T: Crystal Structure Analysis Of Chus, An E. Coli Heme Oxygenase

Heme oxygenases (HOs) catalyze the oxidation of heme to biliverdin, carbon monoxide (CO), and free iron. Iron acquisition is critical for invading microorganisms to enable survival and growth. Here we report the crystal structure of ChuS, which displays a previously uncharacterized fold and is unique compared with other characterized HOs. Despite only 19% sequence identity between the N- and C-terminal halves, these segments of ChuS represent a structural duplication, with a root-mean-square deviation of 2.1 A between the two repeats. ChuS is capable of using ascorbic acid or cytochrome P450 reductase-NADPH as electron sources for heme oxygenation. CO detection confirmed that ChuS is a HO, and we have identified it in pathogenic Escherichia coli O157:H7. Based on sequence analysis, this HO is present in many bacteria, although not in the E. coli K-12 strain. The N- and C-terminal halves of ChuS are each a functional HO.
PDB ID: 1U9TDownload
MMDB ID: 35436
PDB Deposition Date: 2004/8/10
Updated in MMDB: 2005/11
Experimental Method:
x-ray diffraction
Resolution: 2.16  Å
Source Organism:
Similar Structures:
Biological Unit for 1U9T: dimeric; determined by author
Molecular Components in 1U9T
Label Count Molecule
Proteins (2 molecules)
Putative Heme/hemoglobin Transport Protein
Molecule annotation
* Click molecule labels to explore molecular sequence information.

Citing MMDB