1orb
ACTIVE SITE STRUCTURAL FEATURES FOR CHEMICALLY MODIFIED FORMS OF RHODANESEACTIVE SITE STRUCTURAL FEATURES FOR CHEMICALLY MODIFIED FORMS OF RHODANESE
Structural highlights
FunctionTHTR_BOVIN Together with MRPL18, acts as a mitochondrial import factor for the cytosolic 5S rRNA. Only the nascent unfolded cytoplasmic form is able to bind to the 5S rRNA (By similarity). Formation of iron-sulfur complexes and cyanide detoxification. Binds molecular oxygen and sulfur. Evolutionary Conservation![]() Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedIn 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. 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[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences |
|