MECHANISM OF VITAMIN B6-ENZYME INHIBITION BY HORMONES
نویسندگان
چکیده
منابع مشابه
Function of the vitamin B6 group; mechanism of transamination.
The r&e of vitamin Bg in amino acid metabolism has been well established through enzyme studies (l-3) and by the substitution for various amino acids in growth studies (4-6). The coenzyme form, synthetic pyridoxal phosphate (7), functions as the coenzyme for amino acid decarboxylases (S-10), transaminases (2, 3), tryptophan formation (11)) and tryptophan breakdown by tryptophanase (12). The rea...
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The biosynthesis and control of vitamin B6 in bacteria could be studied more easily if an organism which produced large amounts of this family of compounds could be found. Unfortunately, the measurements of bacterial vitamin B6 that have been reported have often failed to include the total extracellular vitamin B6, and thus they do not adequately reflect the total vitamin B6 in the whole cultur...
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Derivatives of phenyl-keto butenoic acids have been reported to be inhibitors of pyruvate decarboxylase, (PDC). The inhibition of transketolase, a thiamine requiring enzyme such as PDF, by meta nitrophenyl derivative of 2-oxo-3-butenoic acid (MNPB) is reported here. These studies indicate that the inhibitor binds to the enzyme at the active site. A two-step inhibition was observed, first th...
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The physiologically active form of vitamin B6, pyridoxal 5'-phosphate (PLP), is known to function as a cofactor in many enzymic reactions in amino acid metabolism. Recent studies have shown that, apart from its role as a coenzyme, PLP acts as a modulator of steroid hormone receptor-mediated gene expression. Specifically, elevation of intracellular PLP leads to a decreased transcriptional respon...
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Substrate channeling has emerged as a common mechanism for enzymatic intermediate transfer. A conspicuous gap in knowledge concerns the use of covalent lysine imines in the transfer of carbonyl-group-containing intermediates, despite their wideuse in enzymatic catalysis. Here we show how imine chemistry operates in the transfer of covalent intermediates in pyridoxal 5'-phosphate biosynthesis by...
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ژورنال
عنوان ژورنال: THE JOURNAL OF VITAMINOLOGY
سال: 1959
ISSN: 0022-5398
DOI: 10.5925/jnsv1954.5.249