Developmental profiles and properties of hepatic peroxisomal apo- and mitochondrial holoalanine:glyoxylate aminotransferase during chick embryogenesis.
Alanine:glyoxylate aminotransferase was present as the apoenzyme in the peroxisomes and as the holoenzyme in the mitochondria in chick embryos. The peroxisomal enzyme predominated in the early stage and gradually decreased during embryonic development and disappeared after hatching. In contrast, the mitochondrial enzyme gradually increased and predominated in the later stage of chick embryos. Peroxisomal alanine:glyoxylate aminotransferase in chick embryos was a single peptide with a molecular weight of about 40,000. The enzyme differed from the mitochondrial enzyme in the embryos, and mammalian alanine:glyoxylate aminotransferases 1 (with a molecular weight of about 80,000 with two identical subunits) and 2 (with a molecular weight of about 200,000 with four identical subunits) in molecular weights and immunological properties. Mitochondrial alanine:glyoxylate aminotransferase in chick embryos had an identical molecular weight and immunologically cross-reacted with mammalian mitochondrial alanine:glyoxylate aminotransferase 2. Pyridoxal 5'-phosphate dissociated easily from the peroxisomal enzyme saturated with pyridoxal 5'-phosphate. Hepatic aspartate:2-oxoglutarate aminotransferase and alanine:2-oxoglutarate aminotransferase in chick embryos, and hepatic alanine:glyoxylate aminotransferases in different animal species were all present as the holoenzyme.
D000410:Alanine Transaminase / Q000302:isolation & purification / Q000378:metabolism*; D000818:Animals; D001051:Apoenzymes / Q000378:metabolism*; D001059:Apoproteins / Q000378:metabolism*; D002642:Chick Embryo; D005779:Immunodiffusion; D007700:Kinetics; D008099:Liver / Q000196:embryology* / Q000201:enzymology; D008830:Microbodies / Q000201:enzymology*; D008930:Mitochondria, Liver / Q000201:enzymology*; D011732:Pyridoxal Phosphate / Q000494:pharmacology; D000637:Transaminases
D001051:Apoenzymes; D001059:Apoproteins; D011732:Pyridoxal Phosphate; D000637:Transaminases; D000410:Alanine Transaminase; C019635:Alanine-glyoxylate transaminase