High impact information on PDC5

• Mutant studies showed that one of the decarboxylases encoded by PDC1, PDC5, PDC6, YDL080c, or YDR380w must be present to allow yeast to utilize alpha-keto-beta-methylvalerate [1].
• Thiamine repression and pyruvate decarboxylase autoregulation independently control the expression of the Saccharomyces cerevisiae PDC5 gene [2].
• We conclude that the stimulation of PDC5 expression in a pdc1delta mutant is not due to a response to thiamine limitation [2].
• Deletion of either of these genes has little or no effect on the specific pyruvate decarboxylase activity, but enzyme activity is undetectable in mutants lacking both PDC1 and PDC5 (S. Hohmann and H. Cederberg, Eur. J. Biochem. 188:615-621, 1990) [3].
• A pdc1-8 mutant was used to isolate spontaneous suppressor mutations, which allowed expression of PDC5 [4].

Biological context of PDC5

• Autoregulation may control the expression of yeast pyruvate decarboxylase structural genes PDC1 and PDC5 [5].
• The predicted amino acid sequences of PDC1 and PDC5 are 88% identical [5].
• Thus, PDC2 is either important for a high basal level of PDC gene expression or it plays a positive role in the autoregulation that controls expression of PDC1 and PDC5 [6].

Associations of PDC5 with chemical compounds

• Consequently, pdc1 delta pdc5 delta double mutants do not ferment glucose and do not grow on glucose medium [7].
• Experiments with cell extracts from S. cerevisiae mutants expressing a single PDC gene demonstrated that both PDC1- and PDC5-encoded isoenzymes can decarboxylate branched-chain 2-oxo acids [8].
• We constructed a metabolically engineered Saccharomyces cerevisiae that has both pyruvate decarboxylase genes (PDC1 and PDC5) disrupted in the genetic background to express two copies of the bovine L-lactate dehydrogenase (LDH) gene [9].

Regulatory relationships of PDC5

• PDC5 is only expressed in pdc1 deletion mutants [5].

Other interactions of PDC5

• Interestingly, the enzymes Pdc1 and Pdc5 are enriched in the nucleus [10].

Analytical, diagnostic and therapeutic context of PDC5

• Two-dimensional gel electrophoresis of whole protein extracts shows that thiamine limitation stimulates the production of THI gene products and of Pdc5p [2].

References