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...

Phosphoenolpyruvate and oxaloacetate are key intermediates at the junction between catabolism and biosynthesis. Alteration of carbon flow at these branch points will affect the growth yield and the formation of products. We attempted to modulate the metabolic flow between phosphoenolpyruvate and oxaloacetate by overexpressing phosphoenolpyruvate carboxylase and phosphoenolpyruvate carboxykinase...

TWO ROUTES FOR SYNTHESIS OF PHOSP~OENOLP~~ATE FROM C4-DICARBOXYLIC AICDS IN ESCHKRICHIA COLI Eric J. Hansen and Elliot Juni Department of Microbiology The University of Michigan Ann Arbor, Michigan 48104 Received June 28,1974 SUMMARY Mutants of s. coli defective in both phosphoenolpyruvate carboxykinase and phosphoenolpyruvate synthetase are unable to use C4-dicarboxylic acids such as suecinate...

Succinate fermentation was investigated in Escherichia coli strains overexpressing Actinobacillus succinogenes phosphoenolpyruvate carboxykinase (PEPCK). In E. coli K-12, PEPCK overexpression had no effect on succinate fermentation. In contrast, in the phosphoenolpyruvate carboxylase mutant E. coli strain K-12 ppc::kan, PEPCK overexpression increased succinate production 6.5-fold.

We have determined the sequence of the mRNA encoding cytosolic phosphoenolpyruvate carboxykinase (GTP) [GTP:oxaloacetate carboxy-lyase (transphosphorylating), EC 4.1.1.32] from the chicken and have deduced the primary structure of the protein. The message for the enzyme is 2762 bases long and encodes a protein of 622 amino acids with a molecular mass of 69,522 daltons. The 5' untranslated regio...

The results are consistent with an inhibition of gluconeogenesis at the level of phosphoenolpyruvate carboxykinase in the rat liver cells. The time-course of the large increases in intracellular malate and aspartate, and decrease in phosphoenolpyruvate, is similar to that of the decrease in glucose output by the cells. The lack of inhibition of glucose production from glycerol or D-fructose is ...

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 a...

The Staphylococcus aureus pckA gene was identified and characterized. A pckA mutant lacked detectable phosphoenolpyruvate carboxykinase activity and grew poorly in the absence of glucose. Both enzymatic activity and pckA promoter activity in wild-type cells grown in the absence of glucose were at least 22-fold greater than activities in cells grown in the presence of glucose.