Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:4.1.1.32 (phosphoenolpyruvate carboxykinase)
 4,204 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Phosphoenolpyruvate carboxykinase (EC 4.1.1.49) from Saccharomyces cerevisiae was purified to homogeneity. The enzyme is composed of four subunits of Mr = 64,000. Specific antibodies against phosphoenolpyruvate carboxykinase were raised in rabbits and purified by affinity chromatography. Phosphoenolpyruvate carboxykinase is rapidly inactivated when glucose is added to cells starved for carbon (Haarasilta, S., and Oura, E. (1975) Eur. J. Biochem. 52, 1-7; Gancedo, C., and Schwerzmann, K. (1976)( ARch. Microbiol. 109, 221-225). In the present study this inactivation has been analyzed by immunochemical techniques. It was found that the loss of catalytic activity is paralleled by a decrease in cross-reacting material which suggests degradation of the enzyme. In the absence of glucose the enzyme is degraded very slowly, which indicates that glucose-induced inactivation cannot simply be due to repression of enzyme synthesis in the presence of a rapid rate of degradation. Experiments with a proteinase-deficient mutant showed that proteinase B, carboxypeptidase Y, and carboxypeptidase S are not involved in the inactivation system.
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PMID:Immunochemical studies on catabolite inactivation of phosphoenolpyruvate carboxykinase in Saccharomyces cerevisiae. 700 22

A new carboxypeptidase (carboxypeptidase S) was found in a Saccharomyces cerevisiae strain lacking carboxypeptidase Y (D. H. Wolf and U. Weiser, Eur. J. Biochem. 73:553-556, 1977). Mutants devoid of carboxypeptidase S activity were isolated from a mutant strain that was also deficient in carboxypeptidase Y. Four mutants were analyzed in detail and fell into one complementation group. The defect segregated 2:2 in meiotic tetrads. Gene dosage experiments indicated that the mutation might reside in the structural gene of carboxypeptidase S. The absence of both enzymes, carboxypeptidases Y and S, did not affect mitotic growth. Ascopore formation was only slightly affected by the absence of both carboxypeptidases. Protein degradation under conditions of nutrient deprivation and under sporulation conditions showed no obvious alteration in the absence of carboxypeptidases Y and S. When a proteinase B mutation, which led to the absence of proteinase B activity and resulted in the partial reduction of sporulation, was introduced into a mutant lacking both carboxypeptidases, the ability of diploid cells to sporulate was nearly completely lost. Mutants lacking both carboxypeptidases were unable to grow on the dipeptide benzyloxycarbonylglycyl-l-leucine as a sole nitrogen source, which indicates an additional function for carboxypeptidases Y and S in supplying nutrients from exogenous peptides. Catabolite inactivation of fructose-1,6-bisphosphatase, cytoplasmic malate dehydrogenase, and phosphoenolpyruvate carboxykinase and inactivation of nicotin-amide adenine dinucleotide phosphate-dependent, glutamate dehydrogenase, events which have been proposed to involve proteolysis in vivo, were not dependent on the presence of carboxypeptidase Y and S. In a mutant lacking both carboxypeptidases, four new proteolytic enzymes with carboxypeptidase activity were detected.
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PMID:Carboxypeptidase S- and carboxypeptidase Y-deficient mutants of Saccharomyces cerevisiae. 702 30

Incubation of partially purified yeast phosphoenolpyruvate carboxykinase (ATP:oxaloacetate carboxy-lyase (transphosphorylating), EC 4.1.1.49) with 5% mercaptoethanol and 0.01% sodium dodecyl sulfate at 37 degrees C results in degradation of the enzyme. The degradation can be partially prevented by addition of proteinase B inhibitor 2 or phenylmethylsulfonyl fluoride, an inhibitor of proteinase B and carboxypeptidase Y. The degradation can be completely inhibited by addition of proteinase B inhibitor 2 together with pepstatin, and inhibitor of proteinase A. Thus it appears that proteolytic activities are firmly attached to phosphoenolpyruvate carboxykinase and are identical with the yeast proteinases A and B. The latter conclusion was supported by experiments using the pure yeast proteinases.
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PMID:Characterization of the proteolytic activity firmly attached to yeast phoshoenolpyruvate carboxykinase. 705 35