Cap 3 – Energ­a, Catlisis y Bios­ntesis JA Carde, PhD Universidad Adventista Alberts et al

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  • Cap 3 Energa, Catlisis y BiosntesisJA Carde, PhDUniversidad AdventistaAlberts et al.

  • 03_01_A series of enzyme.jpgEnzimas

  • 03_02_metabolic pathways.jpg

  • 03_03_Catabolic anabolic.jpg

  • 03_04_Biological structur.jpgEstructuras biolgicas: orden

  • 03_05_Toward disorder.jpgEntropa espontnea diaria

  • 03_06_Second law of thermo.jpg

  • 03_07_forms of energy.jpg

  • 03_12_Oxidation reduction.jpgOxidacion: perdida de e-; que se traduce enDisminucion en los enlaces C-H

  • 03_13_activation energy.jpgEnzimas: ayudan en la clula a empujar las reacciones por sobre la E de activacion

  • 03_14_Lowering activation.jpgMientras mas E por molecula menos moleculas tienen esa energia!!!La presencia de una Enzima hace que un Numero mayor de moleculas tengan la energia para que la reaccion proceda!!!

  • 03_15_Enzymes catalyze.jpgHay una enzima presente PLTSelectivas: catalizan una reaccion especificaRutas especificas: una serie de enzimas presentes determina la ruta metabolica que una molecula X seguira; esto implica: CONTROL

  • 03_16_Enzymes convert.jpgSitio Activo: region en la enzima con caracteristicas unicas para una molecula unica o sea su sutrato.Participan en la reaccion PERO no son alteradas o afectadas.

  • 03_17_Negative positiveDG.jpg

  • 03_18_Reaction coupling.jpg

  • Reacciones E favorables: crean desorden pq disminuyen la E libre del sistema PLT tienen G negativoReacciones E desfavorables: crean orden pq aumentan la E libre del sistema PLT tienen AG positivo

  • Entonces una reaccinYX va de

    YX ; si tiene G-

    o va deYX; si tiene G+

  • Que factores afectan G de una reaccin?- la energa almacenada en cada molcula (potencial qumico)- las concentraciones de las molculas en la mezcla

    Ej: un exceso de Y sobre X favorece laYX, pq habr mas molculas haciendo esa transicin PLT el G ser mas negativo tambin

  • Como yo puedo determinar cuanta diferencia en [ ] se necesita para compensar una disminucin en energa qumica?

    Con un anlisis termodinmico, donde se separa la parte del cambio de energa libre que es dependiente de [ ] de la parte que es independiente de [ ] .

  • *G= AGo + 0.616 ln [X]/[Y] go - depende de las caracterstica intrnsecas de las molculas (en condiciones ideales) + dependiente de las concentraciones * para una reaccin YX , 37oC G Kcal/mol [Y] y [X] concentraciones de estos RT = 0.616 constante y ln log natural

  • *G= AGo + 0.616 ln [X]/[Y]Si las concentraciones de X y Y son 1M; Que pasa con la relacin entre G y AGo ?Si la razn X:Y disminuye, G sera mas negativo, PQ?Cuando la velocidad de ambas reacciones es igual se llega al equilibrio qumico: estado en el que la razon de X y Y se mantiene constante; K = [X]/[Y]; donde K es la constante de equilibrio;punto donde el efecto de las concentraciones balancea el empuje dado a la reaccion por el G, PLT no hay cambio en energia libre que empuje la reaccin hacia ningun lado asi que AG = 0

  • 03_19_Chemical equilibrium.jpg

  • 03_20_binding interactions.jpgRelacion entre K y G

  • 03_25_enzymes performance.jpg

  • 03_26_equilibrium point.jpg

  • 03_30_Activated carriers.jpg

  • 03_31_Mechanical model.jpg

  • 03_32_ATP and ADP cycle.jpg

  • 03_33_terminal phosphate.jpg

  • 03_34_ATP hydrolysis.jpg

  • 03_35_NADPH.jpg

  • 03_36_NADPH to cholesterol.jpg

  • 03_37_Acetyl coenzyme A.jpg

  • 03_38_activated carrier.jpg

  • 03_39_Condensation hydrolysis.jpg

  • 03_40_2_Synthesis polymer.jpg

  • 03_40_3_Synthesis polymer.jpg

  • 03_40_Synthesis polymer.jpg

  • 03_42_Synthesis RNA or DNA.jpg

  • 03_27_Reaction rate data.jpg

  • 03_28_A stopped_flow appar.jpg

  • Inhibidores Inhibitors are compounds which interact with an enzyme to slow down its rate of reaction

    Many toxic compounds are enzyme inhibitors, being toxic because they inhibit enzymes responsible for vital reactions.

    Inhibitors can interact with an enzyme in different ways and enzyme kinetics is a major tool in distinguishing between these mechanisms.

  • Inhibicion CompetitivaIn the presence of a competitive inhibitor the enzyme can bind to the substrate: to form an enzyme-substrate complex,or the inhibitor: to form an enzyme-inhibitor complex.

  • Inhibicion CompetitivaCompetitive inhibitors prevent the substrate from binding to the enzyme and thereby prevent the enzyme from converting it to product. They are mutually exclusive with the substrate so prior binding of the substrate prevents the inhibitor from binding. Consequently competitive inhibitors are inactive at very high substrate concentrations and do not therefore alter the maximal velocity. They are active at low substrate concentrations which is seen as an increase in the slope of the Lineweaver-Burk plot. They reduce the affinity of the enzyme for its substrate; seen as an increase in the Michaelis constant.

  • Inhibicion CompetitivaEffects on Km Km is an indication of enzyme-substrate affinity. In the presence of a competitive inhibitor some enzyme molecules will exist as free enzymes, others as enzyme-inhibitor complexes. So a competitive inhibitor reduces enzyme-substrate affinity, or increases Km. Effects on Vmax Vmax is the velocity at very high substrate concentration. Under these conditions the inhibitor is competed out by the substrate and does not inhibit the enzyme at all. So competitive inhibitors do not slow the reaction at high substrate concentrations and then is no change in Vmax.

  • 03_29_competitive inhibitor.jpg

  • Inhibicion NO-CompetitivaA noncompetitive inhibitor binds to an inhibitor site on the enzyme which is remote from the active site and brings about a conformational change in the active site. In this sense it's very similar to one of the competitive inhibitor types. The difference is that this time the change in the active site is such that it does not prevent substrate binding but, rather, prevents the enzyme from converting the bound substrate to product.

  • Inhibicion NO-CompetitivaEffects on Km A classical noncompetitive inhibitor has no effect whatsoever on substrate binding so the enzyme-substrate affinity, and hence the Km, are unchanged.

    Effects on Vmax Noncompetitive, of both the classical and mixed varieties, inhibit at high substrate concentrations so the Vmax is decreased.

  • Inhibicion DE-CompetitivaProbably the main claim to fame of uncompetitive inhibitors is the frequent confusion of names between them and noncompetitive inhibitors!

    The key feature of these inhibitors is they are incapable of binding to free enzyme.

  • Inhibicion DE-CompetitivaThey can only bind to the enzyme-substrate complex. This could be because the substrate is itself directly involved in binding the inhibitor or because it brings about a conformational change in an inhibitor binding site which was previously incapable of binding the inhibitor.

    Once the inhibitor has bound it prevents the enzyme from turning the substrate into product. Again this could be some kind of direct interaction, or due to a change in conformation of the active site.

  • Inhibicion DE-CompetitivaUncompetitive inhibitors can bind only to enzyme substrate complex, not to free enzyme. As a result they do not inhibit at very low enzyme concentrations. They show an apparent increase in affinity for the substrate as more substrate binds to the enzyme but only in the formation of an abortive ternary complex.

  • Inhibicion DE-CompetitivaEfecto en Km:Disminuye

    Efecto en Vmax:Disminuye

  • Inhibicin

  • Modelo Michaelis-Menten

  • Lineweaver Burke

    Un aspecto practicamente milagroso que distingue las cosas vivas de las no vivas es la bioenrgetica:las cosas vivas son capaees de crear y mantener orden en un universo q tiende al desordenlo hacen por series interminables de reacciones quimicas: metabolistmo= anabolismo + catabolismoQue se necesita; atomos para formar moleculas y Energia De donde se obtienen ambos: del ambiente inanimado

    **03_01_A series of enzyme.jpgLas reacciones celulares ocurren a temp muchos mas altas q las q hay en la cellCada reaccion necesitara un empuje que la ayuda a ocurrir rapidamente PERO a la temp en la q esta la cell sin aumentarla!!este empuje lo proveen las enzimas, que compensan la falta de intermediariosEnzimas aceleran reacciones quimicas son proteinaspueden trabajar en serieconversion de la molecula A en la F*03_02_metabolic pathways.jpgCada reaccion que ocurre es catalizada por una enzima especifica. Estas pueden trabajar en secuencias o en rutas metabolicasCrean una red intrincada y compleja de reacciones interconectadasQue es metabolismo?la suma de todas las reacciones quimicas necesarias para sobrevivir, crecer y reproducirse

    Se divide en Anabolismo y catabolismo

    *03_03_Catabolic anabolic.jpgRutas antagonicas de reacciones quimicas

    Catabolismo: degrada por rutas oxidativas para liberar energia, rompe enlaces, genera monomeros

    Anabolismo usa energia para generar conmpuestos, forma enlaces, genera macromoleculas

    bioquimica estudia reacciones individuales del metabolismo en detalles

    *03_04_Biological structur.jpg Para que se usa la energiaCosas inanimadas tienden a desordenCuerpos muertas se descomponenLas cosas vivas al reves: TIENDEN A generar orden y de mantenerlo a todos los niveles: desde el spot de una mariposa en el ala hasta desde moleculas q forman estruturas mas complejas

    La