The subcellular distribution of rat liver serine-pyruvate aminotransferase.
1. The subcellular distribution of L-serine-pyruvate aminotransferase activity in rat liver was investigated. About 80% was recovered from cell-free homogenates in a 'total-particles' fraction and the remainder in the cytosol. 2. Subfractionation of the particles by differential sedimentation and on sucrose density gradients showed a distribution for serine-pyruvate aminotransferase activity closely matching that observed for mitochondrial marker enzymes. 3. A study of the solubilization of enzymes from combined subcellular particles by digitonin at various concentrations also indicated a common subcellular location for serine-pyruvate aminotransferase and established mitochondrial enzymes. 4. The increase in liver serine-pyruvate amino-transferase activity induced by glucagon injection was accounted for as an increased mitochondrial activity.
D000818:Animals; D004072:Digitonin; D005934:Glucagon / Q000494:pharmacology; D008099:Liver / Q000187:drug effects / Q000201:enzymology*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013347:Subcellular Fractions / Q000187:drug effects / Q000201:enzymology; D000637:Transaminases / Q000378:metabolism*; D014461:Ultracentrifugation
D005934:Glucagon; D000637:Transaminases; C022638:serine-pyruvate aminotransferase; D004072:Digitonin