Non-enzymatic deamination of serine and cysteine is catalyzed by pyridoxal and certain metal salts at 100” (2). This finding suggested that pyridoxal phosphate might be involved in the enzymatic deamination of these amino acids. Vitamin B, has already been implicated in the desulfhydration of cysteine by rat liver (3) and of cysteine and homocysteine by bacteria (4). Several similarities of cys...

1. Evidence is presented for the presence of pyridoxine phosphate oxidase in aqueous extracts of Escherichia coli. Some comparison is made with pyridoxamine phosphate oxidase. 2. Isoniazid and iproniazid were found to combine with pyridoxal phosphate, but isoniazid did not combine with either pyridoxamine phosphate or pyridoxine phosphate. Both oxidase activities were somewhat inhibited by benz...

Pyridoxal BP-phosphate inhibits the binding of the avian progesterone receptor to ATP-Sepharose, probably through a Schiff base interaction. It also blocks other interactions characteristic of the activated or transformed receptor, such as its binding to nuclei, DNA-cellulose, and phosphocellulose. In an attempt to explain these inhibitory effects, we have characterized the progesterone recepto...

Non-enzymatic deamination of serine and cysteine is catalyzed by pyridoxal and certain metal salts at 100” (2). This finding suggested that pyridoxal phosphate might be involved in the enzymatic deamination of these amino acids. Vitamin B, has already been implicated in the desulfhydration of cysteine by rat liver (3) and of cysteine and homocysteine by bacteria (4). Several similarities of cys...

An improved purification of Escherichia coli K12 tryptophanase is presented. It is shown that the apoenzyme crystals, oxidized by exposure to air, can be reactivated by treatment with a reducing agent. The titration of sulfhydryl groups shows that four -SH groups are exposed end two are masked per protomer. The influence of two effecters, monovalent cations and the coenzyme pyridoxal S-phosphat...

Pyridoxal kinase encoded by pdxK gene, is the important key enzyme in salvage pathway of vitamin B6 biosynthesis. The catalyzes phosphorylation 5′ alcohol groups free form into their 5′-phosphate forms that requires metal ion and ATP. have been reported many organisms except thermophilic bacterium. Therefore, this study aimed to clone, express characterize pyridoxal Geobacillus sp. H6a isolated...

Vitamin Be has for some time been implicated in protein metabolism. More recently a specific function of pyridoxal in the coenzome of tyrosine decarboxylase has been found (l), and the discovery of this function extended to include amino acid decarboxylases in general (2, 3). All members of the vitamin Be group (pyridoxine, pyridoxal,” pyridoxamine) are converted into this coenzyme (termed code...

A highly sensitive fluorimetric assay for the measurement of pyridoxal and pyridoxal phosphate in biological tissues is described. The method involves the enzymic hydrolysis of pyridoxal phosphate to pyridoxal. The pyridoxal (free or total) is separated on an anion-exchange column, concentrated by cation-exchange chromatography and reacted with potassium cyanide under slightly alkaline conditio...

Seeking to determine the effect of liver disease associated with Reye's syndrome on the regulation of plasma pyridoxal 5'-phosphate, we measured this compound in plasma from 11 patients with biopsy-proven Reye's syndrome. Its concentrations in plasma are significantly higher [37.5 (SD 6.13) micrograms/L] at the onset of the disease than after treatment [8.50 (SD 2.9) micrograms/L] or in a group...