The enzyme-substrate complex formed between pyridoxamine-pyruvate transaminase (EC 2.6.1.30) and pyridoxal was reduced with NaBH4. After carboxymethylation and tryptic digestion, pyridoxyl-lysine-containing peptides were isolated by a combination of Sephadex and Dowex 50 chromatography. Analysis of these peptides shows the structure around the pyridoxal-binding lysine residues to be Ala-Asp-Ile...

Pyridoxamine-pyruvate aminotransferase is a PLP (pyridoxal 5'-phosphate) (a coenzyme form of vitamin B6)-independent aminotransferase which catalyses a reversible transamination reaction between pyridoxamine and pyruvate to form pyridoxal and L-alanine. The gene encoding the enzyme has been identified, cloned and overexpressed for the first time. The mlr6806 gene on the chromosome of a symbioti...

Photooxidation of supernatant glutamate aspartate transaminase, limited to the stage during which much of the enzyme activity and only histidine residues are destroyed, does not induce gross protein structural changes as judged by ultracentrifugation, optical rotatory dispersion in the ultraviolet region, and microcomplement fixation techniques. Photooxidized apoenzyme has been shown to bind at...

We have proposed a new method which can be applied in assessing the intracellular production of hydrogen peroxide. Using this assay we have examined the hydrogen peroxide generation during the L-glutamate induced oxidative stress in the HT22 hippocampal cells. The detection of hydrogen peroxide is based on two crucial reagents cis-[Cr(C2O4)(pm)(OH2)2]+ (pm denotes pyridoxamine) and 2-ketobutyra...

Evidence for the production in viva from pyridoxine of compounds with increased activity for certain lactic acid bacteria (1) and for the production of similar compounds by amination or oxidation procedures in vitro (2, 3) has been reported. Only a limited number of structures for the compounds resulting from amination or oxidation appeared possible; synthesis (4, 5) of certain of these resulte...