[Study of acid phosphatase II from Pichia guilliermondii yeasts]

Acid phosphatase II (AP II) was isolated from the cell-free extract of Pichia guilliermondii Wickerham ATCC 9058 and partially purified. The enzyme is a non-specific phosphomonoesterase. It hydrolyzes p-nitrohenyl-phophate (NPP), beta-glycerophosphate, glucose-6-phosphate, guanosine-5'-monophosphate, adenosine-5'-monophosphate, cytidine-5'-monophosphate, uridine-5'-monophosphate, alpha-naphtylphosphate, FMN. The order of the substrates corresponds to the degree of their hydrolysis decrease. The Michaelis constant of the enzyme was 1.4-10-3 M for NPP as a substrate, pH optimum was 5.5 and temperature optimum-40C. AP II was strongly inhibited by MoO4-2, F-, inorganic phosphate, Cu2+ and Be2+. The activity of the enzyme in the yeast cells does not change noticeably during growth on media with low and high iron content.