1orb: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
[[Image:1orb.jpg|left|200px]] | [[Image:1orb.jpg|left|200px]] | ||
<!-- | |||
The line below this paragraph, containing "STRUCTURE_1orb", creates the "Structure Box" on the page. | |||
You may change the PDB parameter (which sets the PDB file loaded into the applet) | |||
or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |||
or leave the SCENE parameter empty for the default display. | |||
| | --> | ||
| | {{STRUCTURE_1orb| PDB=1orb | SCENE= }} | ||
}} | |||
'''ACTIVE SITE STRUCTURAL FEATURES FOR CHEMICALLY MODIFIED FORMS OF RHODANESE''' | '''ACTIVE SITE STRUCTURAL FEATURES FOR CHEMICALLY MODIFIED FORMS OF RHODANESE''' | ||
| Line 31: | Line 28: | ||
[[Category: Gliubich, F.]] | [[Category: Gliubich, F.]] | ||
[[Category: Zanotti, G.]] | [[Category: Zanotti, G.]] | ||
[[Category: | [[Category: Thiosulfate:cyanide sulfurtransferase]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 04:11:08 2008'' | |||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | |||
Revision as of 04:11, 3 May 2008
ACTIVE SITE STRUCTURAL FEATURES FOR CHEMICALLY MODIFIED FORMS OF RHODANESE
OverviewOverview
In the course of the reaction catalyzed by rhodanese, the enzyme cycles between two catalytic intermediates, the sulfur-free and the sulfur-substituted (persulfide-containing) forms. The crystal structure of sulfur-free rhodanese, which was prepared in solution and then crystallized, is highly similar to that of sulfur-substituted enzyme. The inactivation of sulfur-free rhodanese with a small molar excess of hydrogen peroxide relies essentially on a modification limited to the active site, consisting of the oxidation of the essential sulfhydryl to sulfenyl group (-S-OH). Upon reaction of the sulfur-free enzyme with monoiodoacetate in the crystal, the Cys-247 side chain with the bound carboxymethyl group is forced into a conformation that allows favorable interactions of the carboxylate with the four peptide NH groups that participate in hydrogen bonding interactions with the transferable sulfur atom of the persulfide group in the sulfur-substituted rhodanese. It is concluded that active site-specific chemical modifications of sulfur-free rhodanese do not lead to significant changes of the protein structure, consistent with a high degree of similarity of the structures of the sulfur-free and sulfur-substituted forms of the enzyme both in solution and in the crystal.
About this StructureAbout this Structure
1ORB is a Single protein structure of sequence from Bos taurus. Full crystallographic information is available from OCA.
ReferenceReference
Active site structural features for chemically modified forms of rhodanese., Gliubich F, Gazerro M, Zanotti G, Delbono S, Bombieri G, Berni R, J Biol Chem. 1996 Aug 30;271(35):21054-61. PMID:8702871 Page seeded by OCA on Sat May 3 04:11:08 2008