Characterization of the Substrate Binding Site in Rat Liver 3α-Hydroxysteroid/Dihydrodiol Dehydrogenase
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چکیده
منابع مشابه
Activation of human liver 3α-hydroxysteroid dehydrogenase by sulphobromophthalein
Human liver contains at least two isoenzymes (DD2 and DD4) of 3α-hydroxysteroid}dihydrodiol dehydrogenase. The NADP(H)-linked oxidoreductase activities of DD4 were activated more than 4-fold by sulphobromophthalein at concentrations above 20 μM and under physiological pH conditions. Sulphobromophthalein did not stimulate the activities of DD2 and human liver aldehyde reductase, which are functi...
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Two rat liver fatty acid synthetase preparations, containing 1.6 and 2.0 mol of 4'-phosphopantetheine/mol of synthetase, showed specific activity of 2006 and 2140 nmol of NADPH oxidized/min per mg of protein respectively. The two synthetase preparations could be loaded with either 3.3-4.4 mol of [1-14] acetate or 2.9-3.7 mol of [2-14C]malonate, by incubation with either [1-14C] acetyl-CoA or [2...
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Succinate dehydrogenase is composed of two subunits, one of molecular weight 70,000, containing FAD in covalent linkage to a histidyl residue of the polypeptide chain, the other subunit of molecular weight 30,000. The fact that substrate, substrate analogs, and oxalacetate prevent inactivation of the enzyme by thiol-specific agents indicates that a thiol group must be present in close proximity...
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In earlier reports from this laboratory, a series of new synthetic substrates for pepsin was described.'-' These compounds are of the general type Z-His-X-YOAI\e4 where X and Y are the residues of amino acids such as L-phenylalanine, p-nitro-L-phenylalanine, L-tyrosine, L-tryptophan, and L-leucine; the enzymic action is limited to the cleavage of the X-Y bond. One of the substrate analogues pre...
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ژورنال
عنوان ژورنال: Journal of Biological Chemistry
سال: 1996
ISSN: 0021-9258
DOI: 10.1074/jbc.271.47.30190