Go to 'thermo-' entry Go to 'dino-' entry Go to 'chondro-' entry Go to 'aero-' entry Go to '-logy' entry Go to 'thaumato-' entry Go to 'nano-' entry Go to '-sophy' entry Go to 'bucco-' entry Go to '-ism' entry Go to '-lysis' entry Go to 'galacto-' entry Go to '-anthropy' entry Go to 'pneumo-' entry Go to '-ploitation' entry Go to '-lithic' entry Go to '-sepalous' entry Go to 'onco-' entry Go to '-parous' entry Go to 'dermato-' entry Go to 'multi-' entry Go to 'dodeca-' entry Go to '-zoon' entry Go to 'vermi-' entry Go to 'crystallo-' entry Go to 'biblio-' entry Go to 'eco-' entry Go to 'juxta-' entry Go to 'facio-' entry
Affixes: the building blocks of English
Affixes: the building blocks of English

-ase

An enzyme.

[The final part of diastase, derived from Greek diastasis, separation.]

Enzymes are substances produced by living organisms which catalyse biochemical reactions. The first named, in the 1830s, was diastase, which appears during the malting of barley and converts starch into sugar (it is now better known as amylase, from Latin amylum, starch); other examples named on its model were zymase (Greek zumē, leaven) and maltase; together these convert the sugar maltose into alcohol. A very large number of other enzymes has been discovered in the period since, of which a few are given in the list below.

Examples of words in -ase
Names are from English nouns unless otherwise stated.

carboxylase catalyses the addition of a carboxyl group to a specified substrate, the reverse process being carried out by decarboxylase carboxyl
cholinesterase one of a group — especially acetylcholinesterase) — which hydrolyses esters of choline choline
hydrolase catalyses the hydrolysis of a particular substrate hydrolysis
isomerase converts a compound to an isomer isomer
lipase catalyses the breakdown of fats to fatty acids and glycerol or other alcohols Greek lipos, fat
polymerase brings about the formation of a particular polymer, especially DNA or RNA polymer
protease breaks down proteins and peptides protein
proteinase or endopeptidase breaks peptide bonds other than terminal ones in a peptide chain protein
reductase promotes the chemical reduction of a specified substance reduce
synthase catalyses the linking together of two molecules, especially without the direct involvement of ATP synthesis
transcriptase catalyses the formation of RNA from a DNA template during transcription with reverse transcriptase doing the opposite transcription

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