plastoquinone

chemical compound

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Last updated

June 17, 2026

Quick Summary

Plastoquinone is a small molecule found in chloroplasts that plays a role in photosynthesis. It is related to vitamin K and is involved in carrying electrons during the light reactions of photosynthesis. Because plastoquinones are lipid-soluble, they can move through membranes.12

Quinones, in general, are cyclic organic compounds with two carbonyl groups in a six-membered ring. They are found in various organisms, including bacteria, fungi, and plants, and can function as biological pigments. The primary reaction of quinones is their reduction to a dihydroxy form.3

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photosynthesis
Quinones
Small molecules called plastoquinones are found in substantial numbers in the lamellae. Like the cytochromes, quinones have important roles in carrying electrons between the components of the light reactions. Since they are lipid soluble, they can diffuse through the membrane. They can carry one or two electrons, and,…
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Small molecules called plastoquinones are found in substantial numbers in the lamellae. Like the cytochromes, quinones have important roles in carrying electrons between the components of the light reactions. Since they are lipid soluble, they can diffuse through the membrane. They can carry one or two electrons, and,…
Read More