A proteolytic enzyme present in milk. Now rare.

Any enzyme that brings about the decomposition of cellulose, esp. by hydrolysis into cellobiose.

An enzyme that catalyses the hydrolysis of a phosphodiester bond of a nucleic acid, cleaving the nucleic acid into smaller units.

an enzyme catalysing the oxidation of hypoxanthine to xanthine and of xanthine to uric acid.

An enzyme which is secreted or acts extracellularly.

Any enzyme that hydrolyses a glucoside, thereby producing glucose; frequently with preceding Greek letter, as α-glucosidase (= maltase, n.), β-glucos…

Any of certain enzymes involved in the breakdown of galactose.

Any enzyme that catalyses the hydrolysis of a nucleoside into its constituent base and sugar. Also: any of various other enzymes involved in the…

Any enzyme which catalyses the hydrolysis of a nucleotide to a nucleoside and phosphate.

an enzyme which catalyses the deamination of adenosine to inosine; abbreviated ADA.

An enzyme that catalyses the hydrolysis of cellobiose into glucose.

= hydrase, n.

An enzyme that activates another substance, esp. an inactive enzyme.

Any of various enzymes that catalyse the transfer of a phosphate group from adenosine triphosphate to glucose or other hexoses as the first step in…

An enzyme that breaks down histamine (by oxidizing the amino group to an aldehyde).

An enzyme found in the human pancreas and elsewhere in the body, which releases kallidin from a plasma precursor and has been used…

The substrate concentration at which the rate of an enzyme-catalysed reaction is half of its maximum value (for a given enzyme concentration), and…

An enzyme which hydrolyses esters of choline and which is concerned with the transmission of neural impulses.

Any of a group of enzymes which bring about the hydrolysis of a phosphodiester bond.

A proteolytic enzyme secreted in the pancreatic juice as chymotrypsinogen n. and activated by trypsin.

Any enzyme that breaks down glycosidic linkages.

A naturally occurring enzyme which catalyses the formation of thiocyanate and sulphite from thiosulphate and cyanide radicals. Also called thiosulphat…

An enzyme that hydrolyses acetylcholine, and is present at synapses and neuromuscular junctions to inactivate it after transmission of a nerve…

A proteolytic enzyme which hydrolyses peptide bonds formed with the nitrogen atom of proline or 4-hydroxyproline, a deficiency of which leads to…

A flavoprotein enzyme reported to catalyse the reduction of dyes by diphosphopyridine nucleotide.

An iron-containing enzyme involved in the Krebs cycle, bringing about the conversion of citrate into isocitrate via an aconitate intermediate.

Any of the enzymes which catalyse the depolymerization of hyaluronic acid, thereby reducing its viscosity and rendering tissue containing it more…

Any enzyme that brings about transamination.

Any enzyme which catalyses an addition reaction between water and a substrate or the reverse process.

Any enzyme which brings about an isomerization reaction; originally applied to two particular enzymes (see quots. 1943 1944).

a peroxidase occurring in milk and saliva.

An enzyme produced by hæmolytic streptococci which activates plasminogen to form plasmin and is given intravenously to dissolve intravascular blood…

An enzyme found in the cells of plants, and of certain bacteria and fungi, which hydrolyses pectin by the removal of methyl ester groups to produce…

= pectinesterase, n.

an enzyme which transfers a phosphate group from ATP to another molecule (esp. creatine); = kinase, n. b.

An enzyme found in garlic and other species of the genus Allium, which when brought into contact with the amino acid alliin (as in the crushing of a…

coenzyme A.

Any of a group of enzymes which bring about the transfer of phosphate groups from one molecule to another.

An enzyme which catalyses the formation of a polymer, esp. a polynucleotide.

Any enzyme that catalyses the transfer of some particular group or molecule from one molecule to another.

An enzyme, usually isolated from the pancreas, which decomposes elastin. Also in combinations, as elastase-inhibitor; elastase-inhibiting adj.

An enzyme which catalyses the hydrolytic cleavage of successive glucose residues from the non-reducing end of a glucan molecule; spec. one which…

Any enzyme that catalyses the transfer of an acetyl group from one molecule to another.

Any enzyme which catalyses the transfer of hydrogen from one organic substrate to another. Cf. dehydrogenase, n.

Any enzyme which catalyses the hydroxylation of a compound.

Any enzyme capable of catalysing the transfer of a phosphate group from adenosine triphosphate (or other nucleoside triphosphate) to another…

An enzyme which catalyses the transfer of a ketol group, esp. the transfer of a two-carbon glycolaldehyde unit between aldose and ketose sugars in…

Any enzyme that catalyses the addition of a group to carbon atoms joined by a double bond, or the converse reaction; also, a synthetase.

either of two lysosomal enzymes which catalyse the hydrolysis of globoside and some gangliosides.

An enzyme which catalyses the translocation of a substance (see translocation, n. 2b).

(a) an enzyme that converts angiotensin I to angiotensin II (= angiotensin converting enzyme n. at compounds) (now historical and rare); (b) any…

an enzyme that converts angiotensin I to angiotensin II; abbreviated ACE.

An enzyme that catalyses a photochemical reaction.

Any of a group of enzymes which bring about the transfer of acetyl groups from one molecule to another.

= adenylate cyclase n. at adenylate, n. compounds.

any of several enzymes that catalyse the formation of cyclic adenosine monophosphate from adenosine triphosphate.

An enzyme which brings about the replication of a nucleic acid; esp. a polymerase which effects the synthesis of a complementary RNA molecule using…

Biochemistry. The enzyme adenosine deanimase.

The polymerase responsible for transcription, which catalyses the formation of RNA from a DNA template.

= adenylate cyclase n. at adenylate, n. compounds.

Any of various enzymes or enzyme systems involved in nucleic acid rearrangement, esp. in site-specific recombination.

= laminaranase, n.

Any enzyme capable of making a nick in one strand of a double-stranded DNA molecule; a nicking enzyme. Cf. nick, n.1 2i.

An enzyme found in the acrosomes of mammalian spermatozoa, which is thought to facilitate penetration of the ovum at fertilization by digesting…

an enzyme that can synthesize DNA using RNA as a template, found esp. in retroviruses (such as HIV); an RNA-dependent DNA polymerase.

An enzyme that catalyses the hydrolysis of cellulose to cellobiose.

An enzyme involved in prostaglandin synthesis that introduces oxygen molecules into arachidonic acid at carbons 9 and 15, forms a peroxide bridge…

Any enzyme which catalyses the hydrolysis of laminaran.

Any of a group of polymerases that bring about the synthesis of DNA or RNA primers (see primer, n.2 3b).

Any of a class of enzymes which bind to a nucleic acid (DNA or RNA) and catalyse the separation of its strands to enable replication or other…

Any of several enzymes which remove iodine atoms one at a time from the two rings of the thyroid hormone, thyroxine.

Any enzyme which catalyses or is necessary for transposition.

Any of a class of enzymes encoded by open reading frames within introns, which are involved (along with endonucleases and reverse transcriptases) in…