enzyme

[en-zahym]

noun

Biochemistry.

1. any of various proteins, as pepsin, originating from living cells and capable of producing certain chemical changes in organic substances by catalytic action, as in digestion.

enzyme

/ ɛnˈzaɪmɪk, ˈɛnzaɪm, ˌɛnzaɪˈmætɪk, -zɪ-, -ˈzɪm- /

noun

1. any of a group of complex proteins or conjugated proteins that are produced by living cells and act as catalysts in specific biochemical reactions

enzyme

1. Any of numerous proteins produced in living cells that accelerate or catalyze the metabolic processes of an organism. Enzymes are usually very selective in the molecules that they act upon, called substrates, often reacting with only a single substrate. The substrate binds to the enzyme at a location called the active site just before the reaction catalyzed by the enzyme takes place. Enzymes can speed up chemical reactions by up to a millionfold, but only function within a narrow temperature and pH range, outside of which they can lose their structure and become denatured. Enzymes are involved in such processes as the breaking down of the large protein, starch, and fat molecules in food into smaller molecules during digestion, the joining together of nucleotides into strands of DNA, and the addition of a phosphate group to ADP to form ATP. The names of enzymes usually end in the suffix –ase.

enzyme

1. A protein molecule that helps other organic molecules (see also organic molecule) enter into chemical reactions with one another but is itself unaffected by these reactions. In other words, enzymes act as catalysts for organic biochemical reactions.

Other Word Forms

• enzymatic adjective

Word History and Origins

Origin of enzyme¹

First recorded in 1880–85; from Medieval Greek énzymos “leavened,” from Greek en- en- ² + zȳ́m(ē) “leaven” + -os, adjective suffix

Word History and Origins

Origin of enzyme¹

C19: from Medieval Greek enzumos leavened, from Greek _en- ² + zumē leaven

Example Sentences

Even though you can activate active dry yeast in milk, certain milk enzymes and proteins can inhibit the individual yeast granules, which contain almost a skin or coating.

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It was during this work that he discovered an enzyme that enabled a virus made of RNA to be copied into DNA, a process known as reverse transcription.

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In APDS, an enzyme produced in the body is "switched on" all the time, disrupting the development of white blood cells and causing the immune system to be disregulated.

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We told the owner that we were destined to try Osmosis’ storied treatment — a so-called “cedar enzyme bath” — and her eyes widened with excitement.

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She found it, characterized it biochemically, genetically and enzymatically, created plants that made too much of it… and then realized that this enzyme was not, in fact, unknown to science.

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Related Words

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• motivation 
• stimulant