Orthophosphorsäuremonoester-Phosphohydrolaseaktivität der repressiblen Pyrohosphat-Phosphohydrolase I von Candida utilis

Two enzymes splitting inorganic pyrophosphate (I and II) have been investigated in Candida utilis. The results indicate that only enzyme I (no considerable thermoinactivation — 10 min, 71 °C-, optimum near pH 2.5, enzyme strongly bound to the cell, high splitting rates in vivo, derepression under phosphate starvation conditions) is also able to split orthophosphoric monoesters. Thus, the enzyme I is an unspecific acid orthophosphoric monoester phosphohydrolase (E. C. 3.1.3.2.).