Enzymatic Breakdown of Polymetaphosphate. IV. The Activation and the Inhibition of the Enzyme.

Abstract

Enzymes prepared from Aspergillus niger (I) and Saccharomyces cerevisiae (II) and catalyzing the breakdown of high molecular wt. polymetaphosphate showed increased activity in the presence of Zn and Mn. Ag and Hg inhibited the activity. Fluoride, cyanide, iodoacetate, arsenite, formaldehyde and taurocholic acid did not affect the activity of I; II was affected by cyanide and arsenite. The sedimentation constant of the enzyme from I increased from 3.2 S to 6.4 S at the optimum pH of 6.6. Other groups than those blocked by Ag were involved in the formation of a substrate-enzyme complex. Electrodialysis caused denaturation of the enzymes.