Enzymatic oxidation of pyridoxamine phosphate to pyridoxal phosphate in rabbit liver.
نویسنده
چکیده
In the course of testing the possible coenzymic function of the phosphorylated vitamin B, derivatives on the synthesis of glucosamine 6-phosphate by a rat liver preparation, the appearance of a yellow color similar to that of pyridoxal 5-phosphate was observed in the samples containing pyridoxamine 5-phosphate. Further investigation has revealed the presence of a soluble enzyme system in extracts of several mammalian tissues which catalyzes the oxidation of PAMP’ to PALP according to the following equation z2
منابع مشابه
The enzymatic oxidation of pyridoxine and pyridoxamine phosphates.
Extracts of rabbit liver and brain are known (1, 2) to oxidize pyridoxine 5-phosphate to pyridoxal 5-phosphate much faster than they oxidize free pyridoxine to pyridoxal. Comparison of the two activities during limited purification indicated that different enzymes catalyzed the two reactions (1). Pogell (3) had shown previously that oxidation of pyridoxamine 5-phosphate was catalyzed by an enzy...
متن کاملKinetic studies of rat liver glutamicalanine transaminase.
With the discovery that pyridoxal phosphate and pyridoxamine phosphate were cofactors for enzymatic transamination, it was proposed that the reaction was biphasic, involving first an amino group transfer from the amino acid substrate to enzymebound pyridoxal phosphate, followed by a transfer of the amino group to the keto acid substrate (for review, see (1)). With the availability of a highly p...
متن کاملMetabolic Interconversions of Different Forms of Vitamin B,*
Tritium-labeled pyridoxamine, pyridoxal S/-phosphate, and pyridoxine 5’-phosphate were prepared and administered intravenously to mice, and the distribution of isotope in liver and carcass between pyridoxine, pyridoxine 5’-phosphate, pyridoxal, pyridoxal S/-phosphate, pyridoxamine, and pyridoxamine 5’-phosphate was determined at different times after administration. The vitamin B6 forms were ex...
متن کاملSerine hydroxymethyltransferase from Escherichia coli: purification and properties.
Serine hydroxymethyltransferase from Escherichia coli was purified to homogeneity. The enzyme was a homodimer of identical subunits with a molecular weight of 95,000. The amino acid sequence of the amino and carboxy-terminal ends and the amino acid composition of cysteine-containing tryptic peptides were in agreement with the primary structure proposed for this enzyme from the structure of the ...
متن کاملReaction of Pyridoxamine - Pyruvate Transaminase Sulfhydryl Reagents
Wherever the point has been examined (e.g. References l-6), pyridoxal phosphate enzymes have been found to require free sulfhydryl groups for activity. The functional role played by these groups, however, has not been clear. In glutamate-oxaloacetate transaminase, which has been studied most extensively, no spectrophotometric or enzymatic evidence for their participation in coenzyme binding was...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- The Journal of biological chemistry
دوره 232 2 شماره
صفحات -
تاریخ انتشار 1958