ACTIVATION BY ELECTROLYTES AND POLYLYSINE OF POLY(A) SYNTHESIS BY CLOSTRIDIUM PERFRINGENS POLYNUCLEOTIDE PHOSPHORYLASE

A modified purification procedure for polynucleotide phosphorylase from Clostridium perfringens is described which yields an enzyme with a very low nucleotide contamination. The activation of poly(A) synthesis by polylysine and electrolytes has been studied in detail. Both polylysine and inorganic salts stimulate the rate of formation of poly(A); they differ in that a lag phase exists in the reaction activated by salt, whereas in the presence of polylysine the reaction is linear from the earliest time measured and proceeds at about twice the rate achieved with salt. The effect of polylysine is dependent on pH and ionic strength. While both salt and polylysine lower the Ks for ADP, the former has only a small effect on the υmax and the latter increases it markedly. Polylysine forms an insoluble complex with the newly formed poly(A) and the extent of reaction is displaced in the direction of polymer synthesis. © 1968.