This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1dj5
From Proteopedia
| Line 1: | Line 1: | ||
| - | [[Image:1dj5.gif|left|200px]] | + | [[Image:1dj5.gif|left|200px]] |
| - | + | ||
| - | '''CRYSTAL STRUCTURE OF R48A MUTANT OF CYTOCHROME C PEROXIDASE WITH N-HYDROXYGUANIDINE BOUND''' | + | {{Structure |
| + | |PDB= 1dj5 |SIZE=350|CAPTION= <scene name='initialview01'>1dj5</scene>, resolution 1.93Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene> and <scene name='pdbligand=HGU:N-HYDROXYGUANIDINE'>HGU</scene> | ||
| + | |ACTIVITY= [http://en.wikipedia.org/wiki/Cytochrome-c_peroxidase Cytochrome-c peroxidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.11.1.5 1.11.1.5] | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''CRYSTAL STRUCTURE OF R48A MUTANT OF CYTOCHROME C PEROXIDASE WITH N-HYDROXYGUANIDINE BOUND''' | ||
| + | |||
==Overview== | ==Overview== | ||
| Line 7: | Line 16: | ||
==About this Structure== | ==About this Structure== | ||
| - | 1DJ5 is a [ | + | 1DJ5 is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1DJ5 OCA]. |
==Reference== | ==Reference== | ||
| - | Unusual oxidative chemistry of N(omega)-hydroxyarginine and N-hydroxyguanidine catalyzed at an engineered cavity in a heme peroxidase., Hirst J, Goodin DB, J Biol Chem. 2000 Mar 24;275(12):8582-91. PMID:[http:// | + | Unusual oxidative chemistry of N(omega)-hydroxyarginine and N-hydroxyguanidine catalyzed at an engineered cavity in a heme peroxidase., Hirst J, Goodin DB, J Biol Chem. 2000 Mar 24;275(12):8582-91. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/10722697 10722697] |
[[Category: Cytochrome-c peroxidase]] | [[Category: Cytochrome-c peroxidase]] | ||
[[Category: Saccharomyces cerevisiae]] | [[Category: Saccharomyces cerevisiae]] | ||
| Line 22: | Line 31: | ||
[[Category: oxidoreductase]] | [[Category: oxidoreductase]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 10:39:13 2008'' |
Revision as of 08:39, 20 March 2008
| |||||||
| , resolution 1.93Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | and | ||||||
| Activity: | Cytochrome-c peroxidase, with EC number 1.11.1.5 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
CRYSTAL STRUCTURE OF R48A MUTANT OF CYTOCHROME C PEROXIDASE WITH N-HYDROXYGUANIDINE BOUND
Overview
Heme enzymes are capable of catalyzing a range of oxidative chemistry with high specificity, depending on the surrounding protein environment. We describe here a reaction catalyzed by a mutant of cytochrome c peroxidase, which is similar but distinct from those catalyzed by nitric-oxide synthase. In the R48A mutant, an expanded water-filled cavity was created above the distal heme face. N-hydroxyguanidine (NHG) but not guanidine was shown to bind in the cavity with K(d) = 8.5 mM, and coordinate to the heme to give a low spin state. Reaction of R48A with peroxide produced a Fe(IV)=O/Trp(.+) center capable of oxidizing either NHG or N(omega)-hydroxyarginine (NHA), but not arginine or guanidine, by a multi-turnover catalytic process. Oxidation of either NHG or NHA by R48A did not result in the accumulation of NO, NO(2)(-), NO(3)(-), urea, or citrulline, but instead afforded a yellow product with absorption maxima of 257 and 400 nm. Mass spectrometry of the derivatized NHA products identified the yellow species as N-nitrosoarginine. We suggest that a nitrosylating agent, possibly derived from HNO, is produced by the oxidation of one molecule of substrate. This then reacts with a second substrate molecule to form the observed N-nitroso products. This complex chemistry illustrates how the active sites of enzymes such as nitric-oxide synthase may serve to prevent alternative reactions from occurring, in addition to enabling those desired.
About this Structure
1DJ5 is a Single protein structure of sequence from Saccharomyces cerevisiae. Full crystallographic information is available from OCA.
Reference
Unusual oxidative chemistry of N(omega)-hydroxyarginine and N-hydroxyguanidine catalyzed at an engineered cavity in a heme peroxidase., Hirst J, Goodin DB, J Biol Chem. 2000 Mar 24;275(12):8582-91. PMID:10722697
Page seeded by OCA on Thu Mar 20 10:39:13 2008
