phosphatase (redirected from Phosphatases)

phosphatase /phos·pha·tase/ (-tās) any of a group of enzymes that catalyze the hydrolytic cleavage of inorganic phosphate from esters.

---

phos·pha·tase (fsf-ts, -tz)

n.

Any of numerous enzymes that catalyze the hydrolysis of esters of phosphoric acid and are important in the absorption and metabolism of carbohydrates, nucleotides, and phospholipids and in the calcification of bone.

---

phosphatase

[fos′fətāz]

an enzyme that acts as a catalyst in chemical reactions involving phosphorus. It is present in serum, semen, the kidney, and the prostate. It is essential in the calcification of bone. See also catalyst, enzyme.

---

phosphatase(s) (fos´ftās),

n a group of enzymes that are distributed throughout most cells and body fluids and are characterized by their ability to hydrolyze a wide variety of monophosphate esters to alcohols and inorganic phosphate.

phosphatase, acid,

n a group of phosphatases (e.g., serum, liver, prostate) with optimal activity below a pH level of 7. Elevated serum levels have been observed in metastatic breast and prostatic cancer; Paget's, Gaucher's, and Niemann-Pick diseases and in myelocytic leukemia.

phosphatase, alkaline,

n a group of phosphatases (e.g., serum, liver, bone) whose optimal activity ranges near a pH level of 9.8. Elevated blood levels occur in Paget's disease and pregnancy, whereas low levels are characteristic of dwarfism and a generalized nutritional protein deficiency.

---

phosphatase

any of a group of enzymes capable of catalyzing the hydrolysis of esterified phosphoric acid, with liberation of inorganic phosphate, found in practically all tissues, body fluids and cells, including erythrocytes and leukocytes.

---

acid phosphatase

a lysosomal enzyme that hydrolyzes phosphate esters liberating phosphate, showing optimal activity at a pH between 3 and 6; found in erythrocytes, prostatic tissue, spleen, kidney and other tissues.

alkaline phosphatase

an isoenzyme showing optimal activity at a pH of about 10; found in bone, liver, kidney, leukocytes, adrenal cortex and other tissues, often used in clinical diagnosis of liver and/or bone damage. Called also AP; see also alkaline phosphatase.

phosphatase inhibitor-1

inhibitor of phosphatase enzymes known to activate glycogen synthesis or inactivate glycogen breakdown. Need to themselves be phosphorylated by cAMP-dependent kinases before they are effective in their inhibitory activity.