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Related to Phosphatase: alkaline phosphatase, acid phosphatase


An enzyme that catalyzes the hydrolysis and synthesis of phosphoric acid esters and the transfer of phosphate groups from phosphoric acid to other compounds.



any of the enzymes of the hydrolase class that catalyze the hydrolysis of phosphoric acid esters in animals, plants, and microorganisms. Phosphatases maintain the phosphate level necessary for various biochemical processes; it may be that they also transport phosphate to the cell.

Depending on the chemical nature of the substrate, phosphatases are divided into monophosphatases, for example, glucose 6-phosphatase, which hydrolyze monoesters of phosphoric acid, and diphosphatases, such as nucleases, which break down the diesters of phosphoric acid. Monophosphatases, in turn, are classified as either specific (interacting with only one substrate) or nonspecific (having a wide range of activity). Depending on the nature of the medium in which their maximum activity is observed, nonspecific monophosphatases are referred to as either alkaline (optimal activity at pH 8–10) or acid (pH 4–6). Alkaline phosphatases are found in animal tissue (intestinal mucosa, placenta, kidneys, bones) and in milk, bacteria, and fungi; acid phosphatases are present in the tissue of the prostate gland, spleen, and liver and in yeasts, bacteria, and higher plants.

The most comprehensive studies have been carried out on the structure and mechanism of activity of the alkaline phosphatase in Escherichia coli. The enzyme is composed of two identical sub-units that function alternately; it contains firmly bonded Zn atoms and has a molecular weight of 80,000. The arrangement of the polypeptide chains is known, and it has been established that the reaction with the substrate passes through a stage of enzyme phosphorylation. A determination of the activity of acid and alkaline phosphatases is important in diagnosing diseases, such as rickets, that are accompanied by an increase in phosphatase activity.


The Enzymes, 3rd ed., vol. 4. New York-London, 1971.


References in periodicals archive ?
Dr Rita Tewari of the University of Nottingham has completed what she describes as a 'Herculean study', has said that the latest study identifies how protein phosphatases regulate parasite development and differentiation and the research provides a systematic functional analysis for all the 30 phosphatases in Plasmodium berghei, which is the parasite responsible for causing malaria in rodents.
Given the methodological limitations noted above, a simple and rapid method to assess the activity of phosphatase of field-grown roots and their ability to mineralise soil organic P is needed.
Dr Dmitry Bulavin said, "Our work on Wip1 phosphatase for over a decade has now revealed several key features of this molecule.
Cytochemical demonstration and measurement of leucocyte alkaline phosphatase activity in normal and pathological states by a modified azo-dye coupling technique.
According to table 3, adding different levels of canola oil to turkey chick's diet have different effects on alkaline phosphatase activity on several regions of small intestine.
Serine/threonine-specific phosphatases can be divided into two major families: phospho protein phosphatase (PPP) members, which include type 1 (PP1), 2A (PP2A) and 2B (PP2B/calcineurin); and protein phosphatase magnesium-dependent (PPM) members, which include protein phosphatase 2C (PP2C) and require [Mg.
An increase in MLC phosphotylation due to reduced activity of myosin phosphatase appears to result in the hypercontraction of blood vessels, which is a characteristic feature of [Ca.
Structure of the human liver/bone/kidney alkaline phosphatase gene.
The last two milestones relate to the scale-up, commercialization and development of an integrated process for alkaline phosphatase purification using ProMetic technology.
Some patients develop fever, anemia, an increase in erythrocyte sedimentation rate, and an elevated serum alkaline phosphatase level.
Since plants can utilise only inorganic phosphorus (Stevenson 1986), organic phosphorus compounds, which mostly originate from plant roots, fungi, and soil microorganisms, must first be hydrolysed by phosphatase enzymes to the inorganic form (Dick et al.