1sk7
From Proteopedia
OCA (Talk | contribs)
(New page: 200px<br /><applet load="1sk7" size="450" color="white" frame="true" align="right" spinBox="true" caption="1sk7, resolution 1.60Å" /> '''Structural Basis for...)
Next diff →
Revision as of 22:33, 24 November 2007
|
Structural Basis for Novel Delta-Regioselective Heme Oxygenation in the Opportunistic Pathogen Pseudomonas aeruginosa
Overview
The Gram-negative bacterium Pseudomonas aeruginosa contains a heme, oxygenase (pa-HO) that primarily oxygenates the delta-meso heme carbon, [Caignan, G. A., Deshmukh, R., Wilks, A., Zeng, Y., Huang, H. W., Moenne-Loccoz, P., Bunce, R. A., Eastman, M. A., and Rivera, M. (2002) J., Am. Chem. Soc. 124, 14879-14892]. This differs from other previously, characterized heme oxygenases, which display regioselectivity for the, alpha-meso heme carbon. Here we report the crystal structure of pa-HO at, 1.60 A resolution and compare it to the 1.50 A structure of nm-HO from, Neisseria meningitidis [Schuller, D. J., Zhu, W., Stojiljkovic, I., Wilks, A., and Poulos, T. L. (2001) Biochemistry 40, 11552-11558]. The crystal, structure of pa-HO maintains the same overall fold as other bacterial and, mammalian heme oxygenases, including a conserved network of, hydrogen-bonded solvent molecules important for dioxygen activation. The, novel delta-regioselectivity of heme oxygenation observed by pa-HO is due, to the heme being rotated by approximately 100 degrees, which places the, delta-meso heme carbon in the same position as the alpha-meso heme carbon, in other heme oxygenases. The main interaction in pa-HO that stabilizes, the unique heme orientation is a salt bridge between Lys132 and the heme, 7-propionate, as well as hydrophobic contacts involving Leu29, Val33, and, Phe189 with the heme methyl and vinyl groups.
About this Structure
1SK7 is a Single protein structure of sequence from Pseudomonas aeruginosa with SO4 and HEM as ligands. Active as Heme oxygenase, with EC number 1.14.99.3 Full crystallographic information is available from OCA.
Reference
Structural basis for novel delta-regioselective heme oxygenation in the opportunistic pathogen Pseudomonas aeruginosa., Friedman J, Lad L, Li H, Wilks A, Poulos TL, Biochemistry. 2004 May 11;43(18):5239-45. PMID:15122889
Page seeded by OCA on Sun Nov 25 00:40:41 2007
