Acid phosphatase of potato tubers (Solanum tuberosum L). Purification, properties, sugar and amino acid composition

摘要: 1. Acid phosphatase (AcPase) from potato tubers was purified by tannic acid fractionation, DEAE-cellulose chromatography, filtration on Bio-Gel P-150 and affinity chromatography Con A-Sepharose. The enzyme 260-fold electrophoretically homogeneous; its mol. mass is about 69 000. 2. carbohydrate component accounts for 16.6% of the total weight includes mannose (5.6%), rhamnose (3.4%), glucose (2.5%), galactose (1.5%) glucosamine (3.6%). In amino composition aspartic acid, glutamic serine glycine account 37.7% residues. 3. Optimum pH at 5.0-5.3. activity reduced half after 30 min incubation 60 degrees C, fully abolished 2 h 70 C. a nonspecific phosphomonoesterase; aromatic phosphomonoesters inorganic pyrophosphate can serve as substrates. Apparent Km values were 1.25 mM 40 p-nitrophenylphosphate pyrophosphate, respectively. inhibited MoO42-, Zn2+, Hg2+ urea. Inhibition caused urea reversible concentration below 9 M.