Phosphoenolpyruvate carboxykinase from guinea - pig liver mitochondria
نویسنده
چکیده
Phosphoenolpyruvate carboxykinase was purified from mitochondria of guinea-pig liver by affinity chromatography on GMP-Sepharose. The enzyme was purified 100fold to a high degree of electrophoretic homogeneity asjudged by detection of a single protein band on sodium dodecyl sulphate/polyacrylamide gels. The yield was about 16%. The Mr of the purified enzyme was estimated to be 68 500 + 680 by analysis on sodium dodecyl sulphate/polyacrylamide gels. Antibodies raised in rabbits against the purified enzyme were highly specific for mitochondrial phosphoenolpyruvate carboxykinase and did not precipitate the cytosolic form of this enzyme from either rat or guinea-pig liver cytosol. The use of this antibody showed that starvation does not increase the amount of the enzyme. However, neonatal-development-dependent increase in its activity is shown to be mediated by accumulation of phosphoenol pyruvate carboxykinase-specific protein.
منابع مشابه
The regulation of nicotinamide adenine dinucleotide-linked substrate oxidation in isolated liver mitochondria.
A mechanism for regulating the rate of NAD-linked substrate oxidation in isolated liver mitochondria was investigated. Addition of oligomycin and a-ketoglutarate to isolated uncoupled rat liver mitochondria oxidizing an NADlinked substrate such as L( -)-palmitylcarnitine plus L-malate caused an abrupt inhibition of oxygen consumption and of citrate, acetoacetate, and /3-hydroxybutyrate synthesi...
متن کاملAcinar zonation of cytosolic but not organelle-bound activities of phosphoenolpyruvate carboxykinase and aspartate aminotransferase in guinea-pig liver.
In human liver, unlike in rat liver, there is no apparent acinar heterogeneity of total cellular activity of phosphoenolpyruvate carboxykinase [Wimmer, Luttringer & Columbi (1990) Histochemistry 93, 409-415]. Since the intracellular compartmentation of phosphoenolpyruvate carbonxykinase differs in rat and human liver, we examined the acinar heterogeneity of cytosolic and organelle-bound activit...
متن کاملMechanism of 3-mercaptopicolinic acid inhibition of hepatic phosphoenolpyruvate carboxykinase (GTP).
The hypoglycemic agent 3-mercaptopicolinic acid inhibits gluconeogenesis from lactate by isolated, perfused livers from fasted rats and guinea pigs. A 3-mercaptopicolinate concentration of 50 muM caused a sharp decrease in glucose synthesis, with virtually complete inhibition at 100 muM. This inhibitory effect was reversed completely when 3-mercaptopicolinate was removed and the rate of glucose...
متن کاملThe activities and intracellular distribution of nicotinamide-adenine dinucleotide phosphate-malate dehydrogenase, phosphoenolpyruvate carboxykinase and pyruvate carboxylase in rat, guinea-pig and rabbit tissues.
1. Measurements are presented of the activity and intracellular distribution of phosphoenolypruvate carboxykinase, pyruvate carboxylase and NADP-malate dehydrogenase in rat, guinea-pig and rabbit liver and kidney cortex, together with previously obtained measurements of these enzymes in adipose tissue. 2. In all three tissues pyruvate carboxylase activity was greatest in the rat and lowest in t...
متن کاملMitochondrial phosphoenolpyruvate carboxykinase (GTP) and the regulation of gluconeogenesis and ketogenesis in avian liver.
Chicken liver synthesizes glucose from lactate and dihydroxyacetone at high rates but pyruvate, glycerol, alanine, and other amino acids are poor glucose precursors. Despite its limited conversion to glucose, 1 m~ pyruvate completely suppressed ketone body synthesis from octanoate by perfused chicken liver, whereas lactate at this concentration had no effect on ketogenesis. Also, increasing the...
متن کامل