Cofactor: Diferenzas entre revisións

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*Os '''orgánicos''' son os [[coencima]]s, que poden ser:
:* '''vitamínicos''' ([[vitamina]]s ou que conteñen na súa estrutura vitaminas), como: vitamina C <ref>{{cite journal |author=Linster CL, Van Schaftingen E |title=Vitamin C. Biosynthesis, recycling and degradation in mammals |journal=FEBS J. |volume=274 |issue=1 |pages=1–22 |year=2007 |pmid=17222174 |doi=10.1111/j.1742-4658.2006.05607.x}}</ref>, [[biotina]] <ref>{{cite journal |author=Jitrapakdee S, Wallace JC |title=The biotin enzyme family: conserved structural motifs and domain rearrangements |journal=Curr. Protein Pept. Sci. |volume=4 |issue=3 |pages=217–29 |year=2003 |pmid=12769720 |doi=10.2174/1389203033487199}}</ref>, coencima A <ref>{{cite journal |author=Leonardi R, Zhang YM, Rock CO, Jackowski S |title=Coenzyme A: back in action |journal=Prog. Lipid Res. |volume=44 |issue=2&ndash;3 |pages=125–53 |year=2005 |pmid=15893380 |doi=10.1016/j.plipres.2005.04.001}}</ref>, [[NADH|NAD<sup>+</sup>]] e [[NADPH|NADP<sup>+</sup>]] <ref name=Pollak>{{cite journal |author=Pollak N, Dölle C, Ziegler M |title=The power to reduce: pyridine nucleotides—small molecules with a multitude of functions |journal=Biochem. J. |volume=402 |issue=2 |pages=205–18 |year=2007 |pmid=17295611 |pmc=1798440 |doi=10.1042/BJ20061638}}</ref>, [[FAD]], [[FMN]] <ref name=Joosten> {{cite journal |author=Joosten V, van Berkel WJ |title=Flavoenzymes |journal=Curr Opin Chem Biol |volume=11 |issue=2 |pages=195–202 |year=2007 |pmid=17275397 |doi=10.1016/j.cbpa.2007.01.010}} </ref> , pirofosfato de tiamina <ref>{{cite journal |author=Frank RA, Leeper FJ, Luisi BF |title=Structure, mechanism and catalytic duality of thiamine-dependent enzymes |journal=Cell. Mol. Life Sci. |volume=64 |issue=7&ndash;8 |pages=892–905 |year=2007 |pmid=17429582 |doi=10.1007/s00018-007-6423-5}}</ref>, etc.
:* '''non vitamínicos''', como: ATP <ref>{{cita libro |autor=Bugg, Tim |título=An introduction to enzyme and coenzyme chemistry |editor=Blackwell Science - Oxford |ano=1997 |páxinas=95 |isbn=0-86542-793-3}}</ref>, S-adenosil-metionina <ref>{{cite journal |author=Chiang P, Gordon R, Tal J, Zeng G, Doctor B, Pardhasaradhi K, McCann P |title=S-Adenosylmethionine and methylation |journal=FASEB J |volume=10 |issue=4 |pages=471–80 |year=1996 |pmid=8647346}}</ref>, coencima B <ref>{{cite journal |author=Noll KM, Rinehart KL, Tanner RS, Wolfe RS |title=Structure of component B (7-mercaptoheptanoylthreonine phosphate) of the methylcoenzyme M methylreductase system of Methanobacterium thermoautotrophicum |journal=Proc. Natl. Acad. Sci. U.S.A. |volume=83 |issue=12 |pages=4238–42 |year=1986 |pmid=3086878 |pmc=323707 |doi=10.1073/pnas.83.12.4238 }}</ref> , [[coencima Q]] <ref>{{cite journal |author=Crane FL |title=Biochemical functions of coenzyme Q10 |journal=Journal of the American College of Nutrition |volume=20 |issue=6 |pages=591–8 |date=1 December 2001|pmid=11771674 |url=http://www.jacn.org/cgi/content/full/20/6/591 }}</ref>, glutation <ref>{{cita libro | título=Significance of glutathione in plant adaptation to the environment| url=http://books.google.com/?id=aX2eJf1i67IC&pg=PA13| autor=Grill D, Tausz T, De Kok LJ| date=2001| publisher=Springer| isbn=1402001789}}[http://books.google.com/?id=aX2eJf1i67IC&pg=PA13]</ref><ref>{{cite journal |author=Meister A, Anderson ME |title=Glutathione |journal=Annu. Rev. Biochem. |volume=52 |issue= |pages=711–60 |year=1983 |pmid=6137189 |doi=10.1146/annurev.bi.52.070183.003431 }}</ref>, hemo <ref>{{cite journal |author=Wijayanti N, Katz N, Immenschuh S |title=Biology of heme in health and disease |journal=Curr. Med. Chem. |volume=11 |issue=8 |pages=981–6 |year=2004 |pmid=15078160 |doi=10.2174/0929867043455521}}</ref>, etc.
 
Tamén se poden clasificar segundo a forza con que se unan á proteína en: [[grupo prostético|grupos prostéticos]], unidos de forma forte e permanente, e [[coencima]]s, unidos máis feblemente. Pero é importante salientar que non hai unha clara división entre unión "feble" e "forte" do cofactor co encima.<ref name=Metzler/> De feito, moitos, como o NAD<sup>+</sup> poden estar fortemente unidos nuns encimas e feblemente noutros.<ref name=Metzler/>. Os cofactores fortemente unidos rexenéranse, en xeral, durante o mesmo ciclo de reacción, entanto que os que están feblemente unidos rexenéranse nunha reacción posterior catalizada por un encima diferente. Neste último caso, o cofactor podería tamén ser considerado un substrato ou cosubstrato.