enzyme

American  

[en-zahym] / ˈɛn zaɪm /

noun

Biochemistry.

• enzymes
  plural

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.

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enzyme British  

/ 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

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enzyme Scientific  

/ ĕn′zīm /

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.

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enzyme Cultural  

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.

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Other Word Forms

Derived Forms

• enzymatic
  adjective

Inflected Forms

Nouns

• enzymes
  plural

Etymology

Origin of enzyme

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

Explanation

An important element in human chemistry, an enzyme is a protein manufactured by a cell, and is a catalyst in various biological functions. For example, enzymes help break down larger molecules of starch, fat, and protein during digestion. The word enzyme was coined by a German physiologist in the late 1800s to name a digestive process that scientists had been observing. The word was later given to the actual agents discovered to spark the reactions, taken from the Greek énzymos, which meant "leavened." (Leavening makes bread rise.) Remember that the word enzyme is spelled with a y and not an i, which makes sense, since when scientists observe chemical processes, they often ask "why?"

Example Sentences

See Examples For:

enzyme enzymes

The medication is a broad-spectrum inhibitor of the viral polymerase, an enzyme the virus needs in order to reproduce.

From Science Daily ● Jul. 24, 2026

As the body attempts to clear methanol - breaking it down or metabolising it in the liver - an enzyme converts it to formaldehyde and formic acid.

From BBC ● Jul. 18, 2026

The first enzyme cuts the long polymer chains at random points, reducing them into shorter sections.

From Science Daily ● Jul. 17, 2026

The answers she found are powerful, like an enzyme to treat HIV that was found in a tree that was discovered because a researcher spoke Samoan.

From Los Angeles Times ● Jul. 2, 2026

Every mutant, they noted, was missing a single metabolic function, corresponding to the activity of a single protein enzyme.

From "The Gene" by Siddhartha Mukherjee

The enzymes helped shape the molecule into its complicated final structure.

From Science Daily ● Aug. 3, 2026

Exercise also boosts antioxidant enzymes in the body, which protect cells from damage.

From The Wall Street Journal ● Jul. 23, 2026

Some microorganisms naturally produce enzymes that cut long polymer chains into smaller fragments.

From Science Daily ● Jul. 17, 2026

The spores became active and began producing the two enzymes.

From Science Daily ● Jul. 17, 2026

They did not answer her, for that would have taken time, and very basic enzymes of survival raced through the bloodstreams of the Meecham children as they headed for their preordained hiding place.

From "The Great Santini" by Pat Conroy

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