Activation of tubulinyl-tyrosine carboxypeptidase by spermine, spermidine, and putrescine

BARRA H.S.,; ARGARAÑA, CE

ACADEMIC PRESS INC ELSEVIER SCIENCE

Año: 1982 vol. 108 p. 654 - 654

permine, spermidine and putrescine produce dose dependent stimulationof the in vitro tubulinyl-tyrosine carboxypeptidase. Maximal stimulationwas obtained with spermine, spermidine or putrescine at 0.06 mM, 1 mMand 6 mM, respectively. At higher concentrations, the enzyme activity wasinhibited. The enzyme was also activated by Mg++; the concentration for maximaleffect was 4-6 mM. The stimulation produced by optimal concentration ofeach amine was unaffected by Mg++ up to 2 mM; higher concentration of Mg++showed inhibitory effect. At optimal Mg++ concentration, the carboxypeptidaseactivity was inhibited by increasing amine concentration. The amines at 0.5or 5 mM did not produce any effect on the incorporation of tyrosine catalyzedby tubulin tyrosine ligase.