Purification, properties and regulation of the level of bovine S-adenosylmethionine decarboxylase during lymphocyte mitogenesis.
S-adenosylmethionine decarboxylase was purified from the livers of calves treated with methylglyoxal bis(guanylhydrazone) to elevate the level of the enzyme. Purified bovine S-adenosylmethionine decarboxylase was similar in specific activity and subunit molecular weight (32,000) to the enzymes previously isolated from rat and mouse. The bovine liver enzyme immunologically crossreacted with S-adenosylmethionine decarboxylase from resting and mitogenically activated bovine lymphocytes. The rate of enzyme synthesis in activated lymphocytes was determined by labeling the cells with [3H]leucine and isolating the radioactive decarboxylase by affinity chromatography and sodium dodecyl sulfate gel electrophoresis. The rate of enzyme synthesis was increased 10-fold by 9 h after mitogen treatment, which accounts for the initial increase in cellular enzymatic activity. There was no further increase in the rate of S-adenosylmethionine decarboxylase synthesis that correlated with a second elevation of activity occurring at approx. 24 h after mitogenic activation. It was concluded that the second increase in enzyme activity was due to lengthening the intracellular half-life of the enzyme by 2-fold.
D012437:Adenosylmethionine Decarboxylase / Q000302:isolation & purification*; D000818:Animals; D002262:Carboxy-Lyases / Q000302:isolation & purification*; D002417:Cattle; D003429:Cross Reactions; D008099:Liver / Q000201:enzymology; D008214:Lymphocytes / Q000166:cytology / Q000201:enzymology*; D008938:Mitosis; D008970:Molecular Weight
D002262:Carboxy-Lyases; D012437:Adenosylmethionine Decarboxylase