The Isozymes of Glutamate-Aspartate Transaminase

Organelle-specific Isozymes of Aspartate-alpha-Ketoglutarate Transaminase in Spinach Leaves.

Four distinct isozymes of aspartate-alpha-ketoglutarate transaminase in a spinach (Spinacia oleracea L.) leaf extract were separated by starch gel electrophoresis. Of the total aspartate-alpha-ketoglutarate transaminase activity, approximately 45% was represented by the chloroplast isozyme, 26% by the cytosol isozyme, 19% by the mitochondrial isozyme, and 3 to 10% by the peroxisomal isozyme. Th...

The interaction of cycloserine with glutamate aspartate transaminase as measured by fluorescence spectroscopy.

The reaction of cycloserine with pyridoxal5-phosphate has been investigated by fluorescence spectroscopy. The substantial change in fluorescence intensity at 450 rnp that follows the reaction of cycloserine with pyridoxal5-phosphate was used to monitor the release of the cofactor from the active site of the enzyme glutamate aspartate transaminase. A kinetic analysis of the fluorescence measurem...

Dffluoro-oxaloacetate with Aspartate Transaminase

Difluoro-oxaloacetate interacts with the aldimine form of aspartate transaminase to give a complex, the dissociation constant ofwhich has been determined spectrophotometrically and by 19F n.m.r. (nuclear magnetic resonance). The 19F n.m.r. line-width-pH and chemical-shift-pH profiles of difluoro-oxaloacetate in the presence of the aldimine form of the enzyme both show inflexion points in the pH...

Urinary aspartate transaminase in childhood.

Interaction between beta-fluoro-oxaloacetate and glutamate-aspartate transaminase of heart mitochondria.