cofactor

American  

[koh-fak-ter] / ˈkoʊˌfæk tər /

noun

1. Biochemistry. any of various organic or inorganic substances necessary to the function of an enzyme.

2. Mathematics.

   1. a prefactor or postfactor.

   2. the product of the minor of a given element of a matrix times −1 raised to the power of the sum of the indices of the row and column crossed out in forming the minor.

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cofactor British  

/ ˈkəʊˌfæktə /

noun

1. maths a number associated with an element in a square matrix, equal to the determinant of the matrix formed by removing the row and column in which the element appears from the given determinant See minor

2. biochem a nonprotein substance that forms a complex with certain enzymes and is essential for their activity. It may be a metal ion or a coenzyme

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cofactor Scientific  

/ kō′făk′tər /

1. A substance, such as a metallic ion or a coenzyme, that must be associated with an enzyme for the enzyme to function. Cofactors work by changing the shape of an enzyme or by actually participating in the enzymatic reaction.

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Etymology

Origin of cofactor

First recorded in 1935–40; co- + factor

Compare meaning

How does cofactor compare to similar and commonly confused words? Explore the most common comparisons:

• cofactor vs. coenzyme

Example Sentences

The scientists also evolved a red light optogenetic system so that yeast cells no longer required an added chemical cofactor.

From Science Daily • Mar. 9, 2026

When intestinal cells absorb cysteine from food, they convert it into CoA, a cofactor that moves into the mucosal lining of the intestine.

From Science Daily • Oct. 23, 2025

Or it could be a cofactor, but on its own it wouldn’t be causal.

From Science Magazine • Jun. 28, 2022

You may also want to consider selenium, a trace mineral that’s a cofactor in a free radical-quenching enzyme called glutathione peroxidase.

From New York Times • Aug. 26, 2021

Opsin pigments are actually transmembrane proteins that contain a cofactor known as retinal.

From Textbooks • Jun. 19, 2013