CRT is the gene cluster responsible for the biosynthesis of carotenoids. Those genes are found in eubacteria, in algae and are cryptic in Streptomyces griseus.
The enzyme taxadiene synthase catalyzes the chemical reaction
In enzymology, a di-trans,poly-cis-decaprenylcistransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a farnesyltranstransferase is an enzyme that catalyzes the chemical reaction.
In enzymology, a geranyltranstransferase is an enzyme that catalyzes the chemical reaction
Damascenones are a series of closely related chemical compounds that are components of a variety of essential oils. The damascenones belong to a family of chemicals known as rose ketones, which also includes damascones and ionones. beta-Damascenone is a major contributor to the aroma of roses, despite its very low concentration, and is an important fragrance chemical used in perfumery.
15-cis-phytoene desaturases, are enzymes involved in the carotenoid biosynthesis in plants and cyanobacteria. Phytoene desaturases are membrane-bound enzymes localized in plastids and introduce two double bonds into their colorless substrate phytoene by dehydrogenation and isomerize two additional double bonds. This reaction starts a biochemical pathway involving three further enzymes called the poly-cis pathway and leads to the red colored lycopene. The homologous phytoene desaturase found in bacteria and fungi (CrtI) converts phytoene directly to lycopene by an all-trans pathway.
9,9'-dicis-zeta-carotene desaturase is an enzyme with systematic name 9,9'-dicis-zeta-corotene:quinone oxidoreductase. This enzyme catalyses the following chemical reaction
4,4'-Diapophytoene desaturase is an enzyme with systematic name 15-cis-4,4'-diapophytoene:FAD oxidoreductase. This enzyme catalyses the following chemical reaction
Phytoene desaturase (neurosporene-forming) is an enzyme with systematic name 15-cis-phytoene:acceptor oxidoreductase (neurosporene-forming). This enzyme catalyses the following chemical reaction
Phytoene desaturase (zeta-carotene-forming) is an enzyme with systematic name 15-cis-phytoene:acceptor oxidoreductase (zeta-carotene-forming). This enzyme catalyses the following chemical reaction
Phytoene desaturase (3,4-didehydrolycopene-forming) is an enzyme with systematic name 15-cis-phytoene:acceptor oxidoreductase (3,4-didehydrolycopene-forming). This enzyme catalyses the following chemical reaction
Phytoene desaturase (lycopene-forming) are enzymes found in archaea, bacteria and fungi that are involved in carotenoid biosynthesis. They catalyze the conversion of colorless 15-cis-phytoene into a bright red lycopene in a biochemical pathway called the poly-trans pathway. The same process in plants and cyanobacteria utilizes four separate enzymes in a poly-cis pathway.
Beta-carotene 3-hydroxylase (EC 1.14.13.129, beta-carotene 3,3'-monooxygenase, CrtZ) is an enzyme with systematic name beta-carotene,NADH:oxygen 3-oxidoreductase . This enzyme catalyses the following chemical reaction
Geranylfarnesyl diphosphate synthase is an enzyme with systematic name geranylgeranyl-diphosphate:isopentenyl-diphosphate transtransferase . This enzyme catalyses the following chemical reaction
Ditrans,polycis-polyprenyl diphosphate synthase is an enzyme with systematic name (2E,6E)-farnesyl-diphosphate:isopentenyl-diphosphate cistransferase . This enzyme catalyses the following chemical reaction
Tritrans,polycis-undecaprenyl-diphosphate synthase is an enzyme with systematic name geranylgeranyl-diphosphate:isopentenyl-diphosphate cistransferase . This enzyme catalyses the following chemical reaction
All-trans-phytoene synthase is an enzyme with systematic name geranylgeranyl-diphosphate:geranylgeranyl-diphosphate geranylgeranyltransferase . This enzyme catalyses the following chemical reaction
The squalene/phytoene synthase family represents proteins that catalyze the head-to-head condensation of C15 and C20 prenyl units (i.e. farnesyl diphosphate and genranylgeranyl diphosphate). This enzymatic step constitutes part of steroid and carotenoid biosynthesis pathway. Squalene synthase EC (SQS) and Phytoene synthase EC (PSY) are two well-known examples of this protein family and share a number of functional similarities. These similarities are also reflected in their primary structure. In particular three well conserved regions are shared by SQS and PSY; they could be involved in substrate binding and/or the catalytic mechanism. SQS catalyzes the conversion of two molecules of farnesyl diphosphate (FPP) into squalene. It is the first committed step in the cholesterol biosynthetic pathway. The reaction carried out by SQS is catalyzed in two separate steps: the first is a head-to-head condensation of the two molecules of FPP to form presqualene diphosphate; this intermediate is then rearranged in a NADP-dependent reduction, to form squalene:
Chlorophyllide a and Chlorophyllide b are the biosynthetic precursors of chlorophyll a and chlorophyll b respectively. Their propionic acid groups are converted to phytyl esters by the enzyme chlorophyll synthase in the final step of the pathway. Thus the main interest in these chemical compounds has been in the study of chlorophyll biosynthesis in plants, algae and cyanobacteria. Chlorophyllide a is also an intermediate in the biosynthesis of bacteriochlorophylls.
