This portal has not been updated since October 2011. Please use the new PC2 web services.
Send us your feedback.  Sign up for Pathway Commons announcements.  RSS Logo RSS Feed

Searched for: REACTOME AND Cytochrome P450 - arranged by substrate type [All Organisms, All Data Sources]

Your search has found 22 relevant records:

Narrow Results:

Pathways (22)Molecules (17)
Showing Results 1 - 10 of 22  | Next 10
0%0%
Pathway: Xenobiotics  from Reactome  [66 molecules]
Of the 50 microsomal CYPs, 15 act on xenobiotics.

Summary:  Of the 50 microsomal CYPs, 15 act on xenobiotics. They all possess wide substrate specificity to cater for most foreign compounds that find their way into the body.

  • ... Curr Drug Metab 3:561-97 ...
  • The cytochrome P450.
  • ... Reactome ...
  • ... reactome.
  • ... possess wide substrate specificity to cater for most foreign compounds that find their way.
  • Authored: Jassal, B, 2008-05-19 12:57:01 ...
  • ... Reactome stable identifier. ... Use this URL to connect to the web page of this instance in Reactome: http://www. ...reactome. ...org/cgi-
0%0%
Pathway: Miscellaneous substrates  from Reactome  [20 molecules]
Approximately a quarter of the 57 human CYPs still remain "orphans" in the sense that their function, expression sites, and regulation are largely not elucidated.

Summary:  Approximately a quarter of the 57 human CYPs still remain "orphans" in the sense that their function, expression sites, and regulation are largely not elucidated. While there is enough experimental evidence to know that all these proteins get made and can catalyze CYP-like reactions in vitro, evidence of in vivo function and substrate specificity is insufficient to allow them to be placed in any of the classes in the functional scheme.

  • ... Reactome ...
  • ... reactome.
  • ... and substrate specificity is insufficient to allow them to be placed in any of the classes in the functional. ... human cytochromes P450 ...
  • ... Use this URL to connect to the web page of this instance in Reactome: http://www. ...reactome. ...org/cgi-
  • ... REACTOME DATABASE ID ...
  • ... Reactome stable identifier.
0%0%
Pathway: Sterols are 12-hydroxylated by CYP8B1  from Reactome  [12 molecules]
Edited: Jassal, B, 2008-05-19 12:57:01.

Summary:  Edited: Jassal, B, 2008-05-19 12:57:01

  • ... : Jassal, B, 2008-05-19 12:57:01 ...
  • ... Cytochrome P450 8B1 (CYP8B1, sterol 12-alpha- hydroxylase) has a broad substrate specificity including a number of 7-alpha- hydroxylated C27 steroids. ...Sterols are 12-hydroxylated by CYP8B1 ...
  • ... Reactome ...
  • ... reactome.
  • ... assignment of the sterol 12alpha-hydroxylase gene (CYP8B1) in human and mouse: eukaryotic cytochrome P-450 gene devoid of introns ...
  • ... Reactome stable identifier.
0%0%
Pathway: FMO oxidizes nucleophiles  from Reactome  [19 molecules]
Flavin-containing monooxygenases (FMOs) are the second family of microsomal oxidative enzymes with broad and overlapping specificity.

Summary:  Flavin-containing monooxygenases (FMOs) are the second family of microsomal oxidative enzymes with broad and overlapping specificity. The major reactions FMOs catalyze are nucleophilic hetero-atom compounds such as nitrogen, sulfur or phosphorus as the hetero-atom to form N-oxides, S-oxides or P-oxides respectively. Despite the functional overlap with cytochrome P450s, the mechanism of action differs. FMOs bind and activate molecular oxygen before the substrate binds to the enzyme (picture). They also require flavin adenosine dinucleotide (FAD) as a cofactor. Unlike cytochrome P450 enzymes, FMOs are heat-labile, a useful way to distinguish which enzyme system is at work for researchers studying metabolism. Also, FMOs are not inducible by substrates, unlike the P450 enzymes.\n(1) NADPH binds to the enzyme and reduces the prosthetic group FAD to FADH2. NADP+ remains bound to the enzyme.\n(2) Incorporation of molecular oxygen to form a hydroperoxide.\n(3) A peroxide oxygen is transferred to the substrate.\n(4) Water is released.\n(5) NADP+ dissociates returning the enzyme to its initial state.\n\nTo date, there are 6 isozymes of FMO (FMO1-6) in humans, the most prominent and active one being FMO3. The FMO6 gene does not encode for a functional enzyme although it has the greatest sequence similarity with FMO3 (71%), whilst the others range from 50-58% sequence similarity with FMO3. FMO1-3 are the ones that exhibit activity towards nucleophiles, the others are insignificant in this respect.

  • ... the functional overlap with cytochrome P450s, the mechanism of action differs. ... FMOs bind and activate molecular oxygen before the substrate binds to the enzyme (picture). ... Unlike cytochrome P450 enzymes, FMOs are heat-labile, a useful way.
  • ... Reactome ...
  • ... reactome.
  • ... are not inducible by substrates, unlike the P450 enzymes.
0%0%
Pathway: Eicosanoids  from Reactome  [16 molecules]
Arachidonic acid is metabolized via three major enzymatic pathways: cyclooxygenase, lipoxygenase, and cytochrome P450.

Summary:  Arachidonic acid is metabolized via three major enzymatic pathways: cyclooxygenase, lipoxygenase, and cytochrome P450. The cytochrome P450 pathway metabolites are oxygenated metabolites of arachidonic acid.

  • ... pathways: cyclooxygenase, lipoxygenase, and cytochrome P450. ... The cytochrome P450 pathway metabolites. ... Cytochrome P450s and other enzymes in drug metabolism and toxicity ...
  • ... Reactome stable.
  • ... Reactome ...
  • ... reactome.
  • ... Use this URL to connect to the web page of this instance in Reactome: http://www. ...reactome. ...org/cgi-
  • ... REACTOME DATABASE ...
0%0%
Pathway: Vitamins  from Reactome  [20 molecules]
Edited: Jassal, B, 2008-05-19 12:57:01.

Summary:  Edited: Jassal, B, 2008-05-19 12:57:01

  • ... varieties: the human cytochromes P450 ...
  • ... Reactome stable identifier.
  • ... Reactome ...
  • ... reactome.
  • ... of this instance in Reactome: http://www. ...reactome. ...org/cgi-
  • ... REACTOME DATABASE ID ...
  • AAPS J 8:E101-11 ...
  • ... Cytochrome P450s and other enzymes in drug metabolism and toxicity 271828 ...
0%0%
Pathway: Steroid hormones  from Reactome  [75 molecules]
Reviewed: D'Eustachio, P, 2008-11-29 15:53:45.

Summary:  Reviewed: D'Eustachio, P, 2008-11-29 15:53:45

  • ... that catalyze these reactions fall into two major classes of proteins: the cytochrome P450 heme-containing.
  • ... Reactome ...
  • ... reactome.
  • ... to the web page of this instance in Reactome: http://www. ...reactome. ...org/cgi-
  • ... REACTOME DATABASE ID ...
  • ... Reactome stable identifier ...
0%0%
Pathway: Phase 1 - Functionalization of compounds  from Reactome  [210 molecules]
Phase 1 of metabolism is concerned with functionalization, that is the introduction or exposure of functional groups on the chemical structure of a compound.

Summary:  Phase 1 of metabolism is concerned with functionalization, that is the introduction or exposure of functional groups on the chemical structure of a compound. This provides a 'handle' for phase 2 conjugating species with which to react with. Many xenobiotics are lipophilic and almost chemically inert (e.g. PAHs) so would not necessarily undergo a phase 2 reaction. Making them more chemically reactive would facilitate their excretion but also increases their chance of reacting with cellular macromolecules (e.g. proteins, DNA). There is a fine balance between producing a more reactive metabolite and conjugation reactions.

  • ... Cytochrome P450s and other enzymes in drug metabolism and toxicity ...
  • ... Reactome stable identifier. ... Use this URL to connect to the web page of this instance in Reactome: http://www. ...reactome.
  • The cytochrome P450 superfamily: biochemistry, evolution and drug. ...Phase 1 - Functionalization of compounds ...
  • ... Reactome ...
  • ... reactome.
  • ... The major oxidoreductase enzyme system is called the P450 monooxygenases.
0%0%
Pathway: Fatty acids  from Reactome  [15 molecules]
Edited: Jassal, B, 2008-05-19 12:57:01.

Summary:  Edited: Jassal, B, 2008-05-19 12:57:01

  • ... Cytochrome P450 enzymes: central players in cardiovascular health and disease ...
  • ... Reactome stable identifier. ... Use this URL to connect to the web page of this instance in Reactome.
  • ... Reactome ...
  • ... reactome.
  • ... of the vasculature by cytochrome P450-derived products of arachidonic acid and other eicosanoids ...
  • El-Kadi. ... REACTOME ...
  • ... Use this URL to connect to the web page of this instance in Reactome ...
0%0%
Pathway: Endogenous sterols  from Reactome  [55 molecules]
A number of CYPs take part in cholesterol biosynthesis and elimination, thus playing an important role in maintaining cholesterol homeostasis.

Summary:  A number of CYPs take part in cholesterol biosynthesis and elimination, thus playing an important role in maintaining cholesterol homeostasis. Under normal physiological conditions, cholesterol intake (diet or synthesized de novo from acetyl CoA) equals cholesterol elimination (degraded to bile salts, secreted in bile and used in steroid hormone synthesis). These processes are under tight regulatory control and any disruption leads to increased cholesterol levels resulting in cardiovacular disease. The CYPs involved in cholesterol homeostasis could serve as potential targets for cholesterol-lowering drugs.

  • ... cytochromes P450 ...
  • ... Reactome stable identifier. ... Use this URL to connect to the web page of this instance in Reactome: http://www. ...reactome. ...org/cgi-
  • ... REACTOME ...
  • ... Reactome ...
  • ... reactome.
  • ... Cytochrome P450s and other enzymes in drug metabolism and toxicity ...