-ase
(Greek: a suffix indicating an enzyme)
From Greek diastasis and then (diast)ase, separation, interval [from dia-, through, apart, plus stasis, a standing]; an amylase that converts starch to maltose. Added to the name of a substance it usually indicates an enzyme that hydrolyzes that substance; for example, proteinases hydrolyze proteins and asparaginase hydrolyzes asparagine.
This suffix is also described as the termination denoting an enzyme, suffixed to the name of the substance (substrate) upon which the enzyme acts; e.g., phosphatase, lipase, and proteinase. It may also indicate the reaction catalyzed, e.g., decarboxylase and oxidase. Enzymes named before the convention was established generally have an -in ending; e.g., pepsin, ptyalin, and trypsin.
anhydrase
An enzyme that catalyzes the removal of water from a compound; most such enzymes are now known as hydrases, hydrolyases, or dehydratases.
colipase
A small protein in pancreatic juice that is essential for the efficient action of pancreatic lipase.
creatinase
An enzyme catalyzing the hydrolysis of creatine to sarcosine and urea.
cyclase
Descriptive name applied to an enzyme that forms a cyclic compound; e.g., adenylate cyclase.
dextrase
Nonspecific term for the complex of enzymes that converts dextrose (D-glucose) into lactic acid.
glutaminase
An enzyme in kidney and other tissues that catalyzes the hydrolysis of L-glutamine to ammonia and L-glutamic acid; an important enzyme for urinary ammonia formation.
peptidase
Any member of subclass of enzymes of the hydrolase class that catalyze the hydrolysis of peptide bonds; it comprises the exopeptidases and endopeptidases; also called peptide hydrolase.
protease
Descriptive term for proteolytic enzymes, both endopeptideases and exopeptidases.
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