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1e71
From Proteopedia
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MYROSINASE FROM SINAPIS ALBA WITH BOUND ASCORBATE
Overview
Myrosinase, an S-glycosidase, hydrolyzes plant anionic, 1-thio-beta-d-glucosides (glucosinolates) considered part of the plant, defense system. Although O-glycosidases are ubiquitous, myrosinase is the, only known S-glycosidase. Its active site is very similar to that of, retaining O-glycosidases, but one of the catalytic residues in, O-glycosidases, a carboxylate residue functioning as the general base, is, replaced by a glutamine residue. Myrosinase is strongly activated by, ascorbic acid. Several binary and ternary complexes of myrosinase with, different transition state analogues and ascorbic acid have been analyzed, at high resolution by x-ray crystallography along with a, 2-deoxy-2-fluoro-glucosyl enzyme intermediate. One of the inhibitors, d-gluconhydroximo-1,5-lactam, binds ... [(full description)]
About this Structure
1E71 is a [Protein complex] structure of sequences from [Sinapis alba] with NAG, ZN, SO4, ASC and GOL as [ligands]. Active as [Transferred entry: 3.2.1.147], with EC number [3.2.3.1]. Structure known Active Sites: ACT, ASC and ZNB. Full crystallographic information is available from [OCA].
Reference
High resolution X-ray crystallography shows that ascorbate is a cofactor for myrosinase and substitutes for the function of the catalytic base., Burmeister WP, Cottaz S, Rollin P, Vasella A, Henrissat B, J Biol Chem. 2000 Dec 15;275(50):39385-93. PMID:10978344
Page seeded by OCA on Tue Oct 30 15:07:15 2007
Categories: Protein complex | Sinapis alba | Transferred entry: 3.2.1.147 | Burmeister, W.P. | ASC | GOL | NAG | SO4 | ZN | Activation | Ascorbate | Family 1 glycosyl hydrolase | Glucosinolate | Myrosinase | Tim barrel
