objective:   intractable epilepsy is a serious neurologic problem with different etiologies. decreased levels of pyridoxal phosphate in central spinal fluid level of patients with intractable epilepsy due to pyridoxine dependency epilepsy were reported. the aim of this study was to compare plasma pyridoxal 5´-phosphate level in patients with intractable and controlled epilepsy. materials   &   ...

glucose 6- phosphate dehydrogenase from streptomyces aureofaciens was purified andinactivated by pyridoxal 5′-phosphate (plp). the inactivation was a pseudo-first order and time-dependentreaction. complete inactivation was achieved at 0.2mm plp within 16 minutes. the type of inhibition wascompetitive with respect to glucose 6- phosphate. spectral characteristics of plp-enzyme complexcorresponde...

interaction of glucose 6-phosphate dehydrogenase from s. aureofaciens with nad+, nadp+and glucose 6-phosphate were investigated using different fluorescent probes. binding of nad+, nadp+and s-nadph to the native enzyme quenched intrinsic protein fluorescence by 100%, 10% and 21%,respectively, from which kd values of nad+ (6.5 mm), nadp+ (92.0 μm) and s-nadph (122.0 μm)were calculated. binding o...

In studies with pyridoxine and other B(6) compounds in blood, the active forms pyridoxal and pyridoxal phosphate were measured by differential assays using Lactobacillus casei. Red cell uptake of tritiated pyridoxine was also measured. A new metabolic pathway for conversion of pyridoxine to active forms was demonstrated in red cells. In vivo studies in normal subjects suggested that pyridoxine ...

The interaction of a variety of pyridoxal analogues with glutamate decarboxylase and aspartate aminotransferase has been studied. Pyridoxal phosphate N-oxide, N-methylpyridoxal phosphate, 3-0-methylpyridoxal phosphate, 4-de(formyl)-4-vinyl pyridoxal phosphate, and pyridoxal analogues which contain modified substituents in position 5 (CH2CHrOPOsHL, CH(CHB)OPOIH2, CHVPOBHL, and CHICH,COOH) are bo...

Although pyridoxal phosphate is known to inhibit gelation of purified hemoglobin S, antisickling activity has never been demonstrated for intact erythrocytes. We incubated washed erythrocytes at 37 degrees C either in buffer alone, or with added pyridoxal phosphate or pyridoxal, washed these cells, suspended them in untreated buffer, and compared the percent modified hemoglobin, the oxygen affi...

Previous studies in vivo and with isolated perfused rat livers have suggested that the deleterious effect of ethanol on hepatic pyridoxal 5'-phosphate metabolism is mediated by acetaldehyde. Inasmuch as acetaldehyde has no effect on the synthesis of pyridoxal phosphate, it has also been postulated that acetaldehyde accelerates pyridoxal phosphate degradation by displacing this coenzyme from bin...

A B S T R A C T Although pyridoxal phosphate is known to inhibit gelation of purified hemoglobin S, antisickling activity has never been demonstrated for intact erythrocytes. We incubated washed erythrocytes at 370C either in buffer alone, or with added pyridoxal phosphate or pyridoxal, washed these cells, suspended them in untreated buffer, and compared the percent modified hemoglobin, the oxy...

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...

The effect of pyridoxal 5'-phosphate on the 1,25-dihydroxyvitamin D3 receptor system has been studied by using pig intestinal chromatin. Pyridoxal 5'-phosphate did not affect the binding of 1,25-dihydroxyvitamin D3 to its receptor extracted from chromatin with hypertonic KCl, although in the presence of pyridoxal 5'-phosphate 1,25-dihydroxyvitamin D3-receptor complexes were not readily precipit...