Alanine release by rat diaphragm muscle in vitro is stimulated by glutamate, valine, leucine and glucose. The stimulation by glutamate and valine (but not leucine) is inhibited by 3-mercaptopicolinate. These results suggest a metabolic route involving phosphoenolpyruvate carboxykinase which directs amino acid carbon skeletons towards pyruvate synthesis for alanine formation.

mTOR pathway activation and hypervascularity have been identified as important characteristics of pancreatic neuroendocrine tumors (pNETs). Agents targeting angiogenesis and mTOR, such as sunitinib and everolimus (RAD001), have been shown to result in progression-free survival of approximately 11 months in patients with advanced pNETs. Novel treatment is needed to extend survival. Mitochondrial...

3- Aminopicolinate , a hyperglycemic agent that activates purified phosphoenolpyruvate carboxykinase in the presence of Fe2+, inhibits glucose synthesis from lactate, pyruvate, asparagine, monomethyl succinate, or glutamine but does not affect that from fructose, dihydroxyacetone, sorbitol, or glycerol in hepatocytes isolated from rats fasted for 24 h. Lactate production from monomethyl succina...

The functional significance of tyrosine 207 of Saccharomyces cerevisiae phosphoenolpyruvate carboxykinase was explored by examining the kinetic properties of the Tyr207Leu mutant. The variant enzyme retained the structural characteristics of the wild-type protein as indicated by circular dichroism, intrinsic fluorescence spectroscopy, and gel-exclusion chromatography. Kinetic analyses of the mu...

The systems which control the levels of the gluconeogenic enzymes in Saccharomyces cerevisiae have been bypassed to ascertain their physiological significance. The coding regions of the genes FBP1 and PCK1, which encode fructose-1,6-bisphosphatase and phosphoenolpyruvate carboxykinase, have been put under the control of the promoter of ADC1 (alcohol dehydrogenase I), a gene not repressed by glu...

Phosphoenolpyruvate carboxykinase has been partially purified from pineapple (Ananas comosus [L.]) leaves. Specific activities obtained show it to be a major activity in this tissue. Above 15 C, the respective activation energies for decarboxylation and carboxylation are 13 and 12 kcal/mol. Below 15 C, there are discontinuities in Arrhenius plots with an associated large increase in activation ...