Adenosín difosfato: Diferenzas entre revisións

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presente no [[ARN]] (no [[ADN]] está presente a desoxiADP). É un [[éster]] do [[ácido fosfórico]] (do que hai dúas unidades) co [[nucleósido]] [[adenosina]]. O ADP consta dun [[pirofosfato]] (formado por dous fosfatos), un azucre de 5 carbonos, a [[ribosa]], e a [[base nitroxenada]] [[adenina]].
 
O ADP é o produto da [[desfosforilación]] do [[ATP]] por acción das [[ATPase]]s. O ADP pode converterse de novo en ATP pola acción das [[ATP sintase]]s. O ATP é unha molécula importante na transferencia de enerxía na célula.<ref name="hyperphysics.phy-astr.gsu.edu">Nave, C.R. Adenosine Triphosphate. Georgia State University: Hyper Physics [serial on the Internet]. 2005 [cited 2007 December 7]. Available from:
http://hyperphysics.phy-astr.gsu.edu/hbase/biology/atp.html</ref> TheA conversionconversión ofdestas thesedúas twomoléculas moleculesxoga playsun apapel criticalfundamental rolepara infornecer supplyingenerxía energya fortodos manyos processesprocesos ofda lifevida.<ref name="hyperphysics.phy-astr.gsu.edu"/> TheA deletionrotura ofdun oneenlace ofanhidro ATP’sentre phosphorusos bondsfosfatos generatesdo approximatelyATP xera aproximadamente 7.,3 kilocalorieskcal perpor MoleMol ofde ATP.<ref name="emc.maricopa.edu">Farabee, M.J. The Nature of ATP. ATP and Biological Energy [serial on the Internet]. 2002 [cited 2007 December 7]. Available from:
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookATP.html</ref> Coa enerxía liberada pola respiración aerobia mitocondrial dos nutrientes o ADP pode ser cargado con outro fosfato e transformado en ATP.<ref name="hyperphysics.phy-astr.gsu.edu"/> Durante a fase luminosa da [[fotosíntese]] a enerxía da luz convértese en enrxía do enlace fosfato (fotofosforilación) convertendo ADP en ATP.<ref name="emc.maricopa.edu"/>
 
Nas [[plaqueta]]s o ADP almacénase en [[corpos densos]] e libérase cando as plaquetas se activan. O ADP interacciona cunha familia de receptores do ADP que se encontran nas plaquetas, chamados P2Y1, [[P2Y12]] e P2X1, que interveñen na activación das plaquetas.<ref>Murugappa S, Kunapuli SP, "The role of ADP receptors in platelet function", ''Front Biosci.'', 2006, 11:1977-86</ref> No sangue o ADP convértese en [[adenosina]] pola acción de ecto-ADPases, o que inhibe unha posterior activación das plaquetas por medio dos receptores de adenosine.
 
ADP is the end-product that results when ATP loses one of its phosphate groups located at the end of the molecule.<ref name="hyperphysics.phy-astr.gsu.edu">Nave, C.R. Adenosine Triphosphate. Georgia State University: Hyper Physics [serial on the Internet]. 2005 [cited 2007 December 7]. Available from:
http://hyperphysics.phy-astr.gsu.edu/hbase/biology/atp.html</ref> The conversion of these two molecules plays a critical role in supplying energy for many processes of life.<ref name="hyperphysics.phy-astr.gsu.edu"/> The deletion of one of ATP’s phosphorus bonds generates approximately 7.3 kilocalories per Mole of ATP.<ref name="emc.maricopa.edu">Farabee, M.J. The Nature of ATP. ATP and Biological Energy [serial on the Internet]. 2002 [cited 2007 December 7]. Available from:
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookATP.html</ref> ADP can be converted, or powered back to ATP through the process of releasing the chemical energy available in food; in humans this is constantly performed via aerobic respiration in the mitochondria.<ref name="hyperphysics.phy-astr.gsu.edu"/> Plants use photosynthetic pathways to convert and store the energy from sunlight, via conversion of ADP to ATP.<ref name="emc.maricopa.edu"/> Animals use the energy released in the breakdown of glucose and other molecules to convert ADP to ATP, which can then be used to fuel necessary growth and cell maintenance.<ref name="hyperphysics.phy-astr.gsu.edu"/>
 
Single nucleotides (ADP) have the ability to catalyze organic reactions. This has relevance for prebiotic studies of the [[RNA world]] and [[DNA world]] hypothesis for the origin of life on Earth.<ref>{{Cite journal|last=Kumar|first=Atul|coauthors=Siddharth Sharma, Ram Awatar Maurya|title=Single Nucleotide-Catalyzed Biomimetic Reductive Amination|journal=Advanced Synthesis and Catalyst|volume=352|pages=2227|year=2010|url=http://onlinelibrary.wiley.com/doi/10.1002/adsc.201000178/abstract|doi =10.1002/adsc.201000178|issue=13}}</ref>