title: Increase of inactive form of aspartate aminotransferase in pyridoxine-deficient rat liver.
abstract: Cytosolic aspartate aminotransferase from rat liver was separated into at least 3 subforms, focused at pH 6.2, 5.9, and 5.7, by isoelectric focusing. Increase of subforms with low pI values was observed in pyridoxine-deficient rat liver. These subforms with low pI values showed low catalytic activities relative to their antigenic activities. The Km values for substrate and optimal pH values of the two main subforms were not significantly different in pyridoxine-deficient and control rat livers. Some conformational change of enzyme in the cytosol of pyridoxine-deficient rat liver was suggested by circular dichroic and fluorescent spectra. The N and C terminals of the enzyme from both pyridoxine-deficient rats and controls were shown to be alanine and glutamine, respectively.
mesh_terms: D000818:Animals; D001219:Aspartate Aminotransferases / Q000302:isolation & purification / Q000378:metabolism*; D003600:Cytosol / Q000201:enzymology; D004591:Electrophoresis, Polyacrylamide Gel; D007525:Isoelectric Focusing; D008099:Liver / Q000201:enzymology*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D026681:Vitamin B 6 Deficiency / Q000201:enzymology*
chemical_list: D001219:Aspartate Aminotransferases