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  

/ ˈɛnzaɪm, -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

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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

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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

Researchers assigned the enzyme a descriptive name based on its chemical function, but its genetic identity remained unknown for more than 30 years.

From Science Daily ● Nov. 5, 2026

Researchers were gradually identifying how the different components of the system worked together, but the unknown enzyme remained a major missing piece.

From Science Daily ● Nov. 5, 2026

While Ma investigated the mysterious enzyme, Lengyel was using zebrafish to study colitis, an inflammatory condition affecting the colon.

From Science Daily ● Nov. 5, 2026

When Ma disabled a gene called DHRS7, the enzyme stopped functioning.

From Science Daily ● Nov. 5, 2026

The power of the organic phosphates, those poisoners of the nerve-protective enzyme cholinesterase, may become greater if the body has first been exposed to a chlorinated hydrocarbon which injures the liver.

From "Silent Spring" by Rachel Carson

Members of the order Xylariales are known for producing a variety of specialized chemical compounds and enzymes capable of breaking down complex molecules in plants.

From Science Daily ● Oct. 26, 2026

Researchers believe similar enzymes may allow 'D-rex' to decompose dead wood and obtain nutrients from it.

From Science Daily ● Oct. 26, 2026

Participants who consumed blueberries regularly experienced a greater and more consistent reduction in depressive symptoms, along with subtle changes in genes associated with gut microbial enzymes.

From Science Daily ● Oct. 18, 2026

This approach allowed them to search for genes that might produce enzymes capable of breaking apart plastic polymers.

From Science Daily ● Oct. 16, 2026

Chang had used those cells to discover enzymes and genes specific to liver cells.

From "The Immortal Life of Henrietta Lacks" by Rebecca Skloot

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