Purification and properties of glycine decarboxylase, a component of the glycine cleavage system, from rat liver mitochondria and immunochemical comparison of this enzyme from various sources.
Glycine decarboxylase, tentatively called P-protein as a constituent of the glycine cleavage system, was purified to near homogeneity from rat liver mitochondria. The purified P-protein was a homodimer with a molecular weight of about 210,000, consisting of identical subunits with a molecular weight of 105,000. In the exchange reaction of the carboxyl carbon of glycine wih CO2 catalyzed by the purified P-protein in the presence of H-protein, the pH optimum was 6.7, Km for glycine was 6.6 mM, and Km for H-protein was 7.4 microM. A specific rabbit antibody against the purified rat liver P-protein was prepared. Ouchterlony double diffusion analysis and immunoinhibition experiments using this antibody revealed immunological cross-reactivity among the P-proteins from various species of animals such as carp, frog, snake, chicken, bovine, and human, suggesting a quite conservative evolution of the glycine cleavage system.
D000594:Amino Acid Oxidoreductases / Q000302:isolation & purification / Q000378:metabolism*; D000818:Animals; D003429:Cross Reactions; D005998:Glycine / Q000302:isolation & purification / Q000378:metabolism; D050961:Glycine Decarboxylase Complex H-Protein; D050841:Glycine Dehydrogenase (Decarboxylating); D006801:Humans; D005779:Immunodiffusion; D007700:Kinetics; D046911:Macromolecular Substances; D008297:Male; D008930:Mitochondria, Liver / Q000201:enzymology*; D008970:Molecular Weight; D051381:Rats; D013045:Species Specificity
D050961:Glycine Decarboxylase Complex H-Protein; D046911:Macromolecular Substances; D000594:Amino Acid Oxidoreductases; D050841:Glycine Dehydrogenase (Decarboxylating); D005998:Glycine