Cytochrome P450, family 16, also known as CYP16, is an animal cytochrome P450 monooxygenase family. This family was the last vertebrate CYP family recognized, [1] and is absent from the mammal and zebrafish genome, but found in other fish and many invertebrates including some very old branches, such as Trichoplax and Oscarella carmela . Synteny mapping of CYP16 family members showing linkages to CYP26 family members, means the tetrapod's CYP26 may evolved from CYP16 of fish. [2]
In the past, CYP16 family refers to some nematoda (roundworms) genes, which have been discontinued and changed to the Cytochrome P450, family 13, subfamily B (CYP13B), because its genetic relationship with the subfamily CYP13A. [3]
Cytochromes P450 (CYPs) are a superfamily of enzymes containing heme as a cofactor that functions as monooxygenases. In mammals, these proteins oxidize steroids, fatty acids, and xenobiotics, and are important for the clearance of various compounds, as well as for hormone synthesis and breakdown. In 1963, Estabrook, Cooper, and Rosenthal described the role of CYP as a catalyst in steroid hormone synthesis and drug metabolism. In plants, these proteins are important for the biosynthesis of defensive compounds, fatty acids, and hormones.
Cytochrome P450 2A6 is a member of the cytochrome P450 mixed-function oxidase system, which is involved in the metabolism of xenobiotics in the body. CYP2A6 is the primary enzyme responsible for the oxidation of nicotine and cotinine. It is also involved in the metabolism of several pharmaceuticals, carcinogens, and a number of coumarin-type alkaloids. CYP2A6 is the only enzyme in the human body that appreciably catalyzes the 7-hydroxylation of coumarin, such that the formation of the product of this reaction, 7-hydroxycoumarin, is used as a probe for CYP2A6 activity.
Omega oxidation (ω-oxidation) is a process of fatty acid metabolism in some species of animals. It is an alternative pathway to beta oxidation that, instead of involving the β carbon, involves the oxidation of the ω carbon. The process is normally a minor catabolic pathway for medium-chain fatty acids, but becomes more important when β oxidation is defective.
Cytochrome P450 2A13 is a protein that in humans is encoded by the CYP2A13 gene.
Cytochrome P450 2F1 is a protein that in humans is encoded by the CYP2F1 gene.
CYP4X1 is a protein which in humans is encoded by the CYP4X1 gene.
CYP4F11 is a protein that in humans is encoded by the CYP4F11 gene. This gene encodes a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and other lipids. This gene is part of a cluster of cytochrome P450 genes on chromosome 19. Another member of this family, CYP4F2, is approximately 16 kb away. Alternatively spliced transcript variants encoding the same protein have been found for this gene.
CYP2A7 is a protein that in humans is encoded by the CYP2A7 gene.
ERG5 or Sterol 22-desaturase is a cytochrome P450 enzyme in the ergosterol biosynthesis pathway of fungi Saccharomyces cerevisiae, with the CYP Symbol CYP61A1. CYP61A1 is one of only three P450 enzyme found in baker's yeast, the other two are CYP51F1 and CYP56A1. The ortholog in Schizosaccharomyces pombe, was named CYP61A3 for historical reasons, and is only one of two P450 enzyme found with CYP51F1. ERG5 catalyzes the C22-C23 double bond formation on the sterol side chain of ergostatrienol to convert it into ergostatetraenol, then the C24 double bond of ergostatetrenol will be hydrogenation reduced into ergosterol by ERG4.
The Cyp11c1 is a fish gene encoding a CYP450 enzyme, which was originally found in Zebrafish, this enzyme mainly catalyze the formation of cortisol and 11-Ketotestosterone (11-KT). 11-KT is the endogenous androgen in zebrafish. CYP11C is the orthologous to CYP11B, tetrapod's CYP11B1 evolved from CYP11C1 of fish, and CYP11B/11C are the ohonologues to CYP11A, which duplicated during 2R event.
Cytochrome P450, family 55, also known as CYP55, is a cytochrome P450 family in fungi supposed to derived from horizontal gene transfer of Actinomycetes CYP105 family member in the ancestor of all Dikarya. The first gene identified in this family is the CYP55A1 from Fusarium oxysporum encoding the NADPH dependent reductase of nitrous oxide.
Cytochrome P450, family 710, also known as CYP710, is a plant cytochrome P450 monooxygenase family, the proteins encoded by its family members are mainly sterol 22-desaturase, which was widely distributed in plants, and take participate in Phytosteroidogenesis. CYP710 family is considered to be the plant orthologous of fungi CYP61 family, which is lost in animal. The CYP61/CYP710 ancestor gene diverged from a gene duplication of ancestor CYP51 in early eukaryotes
Cytochrome P450, family 105, also known as CYP105, is a cytochrome P450 monooxygenase family in bacteria, predominantly found in the phylum Actinomycetota and the order Actinomycetales. The first three genes and subfamilys identified in this family is the herbicide-inducible P-450SU1 and P-450SU2 from Streptomyces griseolus and choP from Streptomyces sp's cholesterol oxidase promoter region.
Cytochrome P450, family 11, also known as CYP11, is a chordate cytochrome P450 monooxygenase family. This family contains many enzymes involved in steroidogenesis, such as Cholesterol side-chain cleavage enzyme (CYP11A1), Steroid 11β-hydroxylase (CYP11B1) and Aldosterone synthase (CYP11B2). CYP11 can be divided into A to E five subfamilies, and CYP11A are the ohonologues to CYP11C, which duplicated during 2R event, and the tetrapod's CYP11B evolved from CYP11C of its fish ancestors, CYP11D and F found in amphioxus. These are not the typical CYP subfamilies, which share at least 40% amino acid identity, members between CYP11A and B subfamily are only 37.5-38.8% identical, and the CYP11D and E genes seen in modern lancelet is 39% identical to catfish CYP11A1.
Cytochrome P450, family 9, also known as CYP9, is a cytochrome P450 family found in Insect genome, CYP9 and insect CYP6 family belong to the same clan as mammalian CYP3 and CYP5 families. The first gene identified in this family is the CYP9A1 from the Heliothis virescens, which is involved in thiodicarb insecticide resistance. Subfamily CYP9A in Lepidopteran play important roles in insecticide resistance, can metabolize esfenvalerate efficiently.
Cytochrome P450, family 18, also known as CYP18, is an animal cytochrome P450 family found in insect genomes. It is involved in insecticide resistance. The first member gene identified was CYP18A1, from a Drosophila melanogaster fly, acting as a dimethylnitrosamine demethylase.
Cytochrome P450, family 6, also known as CYP6, is a cytochrome P450 family found in Insect genome. CYP6 and CYP9, another insect CYP family, belong to the same clan as mammalian CYP3 and CYP5 families.
Cytochrome P450, family 13, also known as CYP13, is a nematoda cytochrome P450 monooxygenase family. The first gene identified in this family is the CYP13A1 from the Caenorhabditis elegans.
Cytochrome P450, family 23, also known as CYP23, is a nematoda cytochrome P450 monooxygenase family. The first gene identified in this family is the CYP23A1 from the Caenorhabditis elegans, is a homolog of the human gene CYP7B1.
Cytochrome P450, family 26, also known as CYP26, is an mammal cytochrome P450 monooxygenase family found in human genome. There are three members in the human genome, CYP26A1, CYP26B1 and CYP26C1. Synteny mapping of CYP26 family members showing linkages to CYP16 family members of many invertebrates, means the tetrapod's CYP26 may evolved from CYP16 of fish.