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...

Although hemodynamic and metabolic factors are individually implicated in the development of diabetic nephropathy, their interaction has not been defined clearly. In this study, the effects of angiotensin II (Ang II) and advanced glycation end products (AGE) both individually on each other are explored and compared. In the first study arm, Sprague-Dawley rats received a continuous infusion of A...

(1) showed that pyridoxal-5'-phosphate (a phos-phorylated derivative of vitamin B6) is essential for serum aspartate trans-aminase (AST) activity.This coen-zyme is bound to an amino group of the enzyme during transfer,becoming pyridoxamine phosphate (2). In 1954, Karmen et al. (3) described a practical method of measuring AST activity. Although they gave no data, they did add buffered pyridoxal...

An approach to the determination of the complete stereochemistry of enzymatic transamination is described. Stereospecificity in the enzymatic labilization of one of the 4-methylene protons of pyridoxamine has been demonstrated in the transamination of pyridoxamine catalyzed by apoglutamate-oxaloacetate transaminase. Both enantiomers of the 4-(CHD-NH2) pyridoxamine have been prepared. These comp...

Diabetic nephropathy remains the most common cause of ESRD, accounting for more than 40% of patients treated with dialysis. The standard therapy fordiabetic nephropathy consists of early detection, aggressive glycemic control, and treatment of hypertension and proteinuria using renin-angiotensin system (RAS) blockade. Both angiotensin converting enzyme inhibitors (ACEIs) and angiotensin recepto...

Accurate prediction of thermodynamic constants of chemical reactions in solution is one of the current challenges in computational chemistry. We report a scheme for predicting stability constants (log β) and pKa values of metal complexes in solution by means of calculating free energies of ligand- and proton-exchange reactions using Density Functional Theory calculations in combination with a c...