Acid phosphomonoesterase

Acid phosphatase (acid phosphomonoesterase, EC 3.1.3.2) also catalyzes the hydrolysis of phosphoric acid monoesters but with an acidic pH optimum. It has broad specificity and catalyzes transphosphorylations. Acid phosphatases are a quite heterogeneous group with monomeric, dimeric, larger glycoprotein, and membrane-bound forms. Acid phosphatase activity is present in the heart, liver, bone, prostate, and seminal fluid. Prostate carcinomas produce large quantities of acid phosphatase, and the enzyme is, therefore, used as a biomarker [141]. 

Acid phosphomonoesterase Hydrolysis of phosphoric acid esters Reduce heat stability of milk cheese ripening... 

Milk contains several phosphatases, the principal ones being alkaline and acid phosphomonoesterases, which are of technological significance, and ribonuclease, which has no known function or significance in milk. The alkaline and acid phosphomonoesterases have been studied extensively (see Andrews (1993) for references). 

Acid phosphomonoesterase (EC 3.1.3.2). Milk contains an acid phosphatase which has a pH optimum at 4.0 and is very heat stable (LTLT pasteurization causes only 10-20% inactivation and 30 min at 88°C is required for full inactivation). Denaturation of acid phosphatase under UHT conditions follows first-order kinetics. When heated in milk at pH 6.7, the enzyme retains significant activity following HTST pasteurization but does not survive in-bottle sterilization or UHT treatment. The enzyme is not activated by Mg2+ (as is alkaline phosphatase), but it is slightly activated by Mn2+ and is very effectively inhibited by fluoride. The level of acid phosphatase activity in milk is only about 2% that of alkaline phosphatase activity reaches a sharp maximum 5-6 days post-partum, then decreases and remains at a low level to the end of lactation. 

The sedimentation coefficient of spleen exonuclease, measured by centrifugation in a sucrose density gradient, using cytochrome c as the reference protein, was 4.6 S 11). The enzyme is eluted from Sephadex G-100 between acid phosphomonoesterase (s = 5.6 S) and acid DNase (s = 3.4 S). 

Minute amounts of the acid phosphomonoesterases have also been found to occur in the pancreas, in skeletal and heart muscle, and in the mucosa of the small intestines. 

Relative Rate of Hydrolysis of Several Substrates by Spleen Acid Phosphomonoesterase -6... 

R. Weimberg and W. L. Orton (1965). Synthesis and breakdown of the polyphosphate fraction and acid phosphomonoesterase of Saccharomyces mellis and their location in the cell. J. Bacteriol., 89, 740-742. 

Ostrowski, W., Wasyl, Z., Weber, M., Guminska, M., and Luchter, E., The role of neuraminic acid in the heterogeneity of acid phosphomonoesterase from the human prostate gland. Biochim. Biophys. Acta 221, 297-306 (1970). 

Chersi A., Bernard A., Bernard G. (1966). Studies on acid hydrolases. IE Isolation and properties of spleen acid phosphomonoesterase. Biochim. Biophys. Acta 129 11-22. 

Plant phytases have all of the characteristics of a nonspecific acid phosphomonoesterase with broad substrate specificity (73). 

Acid phosphatase [Acid phosphomonoesterase, Phos-phomonoesterase, Glycerophosphatase] (3.1.3.2) is present. 

Glucuronidase, phospholipase A, cathepsins, aryl-sulfatase, o-glucosidase, acid phosphomonoesterase... 

Cathepsin C is inhibited by excess substrate. Numerous examples of product inhibition of enzyme action are known. Phosphate inhibition of acid phosphomonoesterase activity is well documented (Chersi et al.. 

Nannipieri et al. have used neutral pyrophosphate buffer to extract hydrolases from soils. Maximal acid phosphomonoesterase activities of extracts were achieved after 2-6 hours extraction of soils and were equivalent to 31-66% of the activities of the respective unextracted soils. Phosphatase activities for extracts were directly correlated with C and N contents and were relatively thermostable in crude extracts losing little activity after exposure for 2h at 80°C, whereas under the same conditions a... 

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