Carotenoids are yellow, orange, and red organic pigments that are produced by plants and algae, as well as several bacteria, archaea, and fungi. Carotenoids give the characteristic color to pumpkins, carrots, parsnips, corn, tomatoes, canaries, flamingos, salmon, lobster, shrimp, and daffodils. Over 1,100 identified carotenoids can be further categorized into two classes – xanthophylls and carotenes.
β-Carotene (beta-carotene) is an organic, strongly coloured red-orange pigment abundant in fungi, plants, and fruits. It is a member of the carotenes, which are terpenoids (isoprenoids), synthesized biochemically from eight isoprene units and thus having 40 carbons. Among the carotenes, β-carotene is distinguished by having beta-rings at both ends of the molecule. β-Carotene is biosynthesized from geranylgeranyl pyrophosphate.
The ionones, from greek ἴον ion "violet", are a series of closely related chemical substances that are part of a group of compounds known as rose ketones, which also includes damascones and damascenones. Ionones are aroma compounds found in a variety of essential oils, including rose oil. β-Ionone is a significant contributor to the aroma of roses, despite its relatively low concentration, and is an important fragrance chemical used in perfumery. The ionones are derived from the degradation of carotenoids.
Apocarotenal, or trans-β-apo-8'-carotenal, is a carotenoid found in spinach and citrus fruits. Like other carotenoids, apocarotenal plays a role as a precursor of vitamin A, even though it has 50% less pro-vitamin A activity than β-carotene. The empirical chemical formula for apocarotenal is C30H40O.
Carotenoid oxygenases are a family of enzymes involved in the cleavage of carotenoids to produce, for example, retinol, commonly known as vitamin A. This family includes an enzyme known as RPE65 which is abundantly expressed in the retinal pigment epithelium where it catalyzed the formation of 11-cis-retinol from all-trans-retinyl esters.
Catechol 2,3-dioxygenase (EC 1.13.11.2, 2,3-pyrocatechase, catechol 2,3-oxygenase, catechol oxygenase, metapyrocatechase, pyrocatechol 2,3-dioxygenase) is an enzyme with systematic name catechol:oxygen 2,3-oxidoreductase (decyclizing). This enzyme catalyses the following chemical reaction
In enzymology, beta-carotene 15,15'-dioxygenase, (EC 1.13.11.63) is an enzyme with systematic name beta-carotene:oxygen 15,15'-dioxygenase (bond-cleaving). In human it is encoded by the BCDO2 gene. This enzyme catalyses the following chemical reaction
In enzymology, an acetylacetone-cleaving enzyme (EC 1.13.11.50) is an enzyme that catalyzes the chemical reaction
Apo-beta-carotenoid-14',13'-dioxygenase (EC 1.13.11.67 is an enzyme that catalyzes the chemical reaction
Beta-apo-4'-carotenal oxygenase (EC 1.2.1.82, beta-apo-4'-carotenal dehydrogenase, YLO-1, carD (gene)) is an enzyme with systematic name 4'-apo-beta,psi-carotenal:NAD+ oxidoreductase. This enzyme catalyses the following chemical reaction:
9-cis-epoxycarotenoid dioxygenase (EC 1.13.11.51, nine-cis-epoxycarotenoid dioxygenase, NCED, AtNCED3, PvNCED1, VP14) is an enzyme in the biosynthesis of abscisic acid (ABA), with systematic name 9-cis-epoxycarotenoid 11,12-dioxygenase. This enzyme catalyses the following chemical reaction
Torulene dioxygenase (EC 1.13.11.59, CAO-2, CarT) is an enzyme with systematic name torulene:oxygen oxidoreductase. This enzyme catalyses the following chemical reaction
9-cis-beta-carotene 9',10'-cleaving dioxygenase (EC 1.13.11.68, CCD7 (gene), MAX3 (gene), NCED7 (gene)) is an enzyme with systematic name 9-cis-beta-carotene:O2 oxidoreductase (9',10'-cleaving). This enzyme catalyses the following chemical reaction
Carlactone synthase (EC 1.13.11.69, CCD8 (gene), MAX4 (gene), NCED8 (gene)) is an enzyme with systematic name 9-cis-10'-apo-beta-carotenal:O2 oxidoreductase (14,15-cleaving, carlactone-forming). This enzyme catalyses the following chemical reaction
CCD8 (gene) may refer to:
NCED8 (gene) may refer to:
All-trans-10'-apo-beta-carotenal 13,14-cleaving dioxygenase (EC 1.13.11.70, CCD8 (gene), MAX4 (gene), NCED8 (gene)) is an enzyme with systematic name all-trans-10'-apo-beta-carotenal:O2 oxidoreductase (13,14-cleaving). This enzyme catalyses the following chemical reaction
Carotenoid-9',10'-cleaving dioxygenase (EC 1.13.11.71, BCO2 (gene), beta-carotene 9',10'-monooxygenase (misleading)) is an enzyme with systematic name all-trans-beta-carotene:O2 oxidoreductase (9',10'-cleaving). This enzyme catalyses the following chemical reaction
All-trans-8'-apo-beta-carotenal 15,15'-oxygenase (EC 1.14.99.41, Diox1, ACO, 8'-apo-beta-carotenal 15,15'-oxygenase) is an enzyme with systematic name all-trans-8'-apo-beta-carotenal:oxygen 15,15'-oxidoreductase (bond-cleaving). This enzyme catalyses the following chemical reaction
Zeaxanthin 7,8-dioxygenase (EC 1.14.99.42, zeaxanthin 7,8(7',8')-cleavage dioxygenase, CsZCD) is an enzyme with systematic name zeaxanthin:oxygen oxidoreductase (7,8-cleaving). This enzyme catalyses the following chemical reaction
