ENZIMAS LEHNINGER

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ENZIMAS: HISTORIA

• Spallanzani 1783• Kühne 1836 1878• Swann 1836• Berzelius 1835• Pasteur 1850• Buchner 1897• Fischer 1894• Michaellis 1900• Sumner 1926• Northrop 1935

Ribonucleasa A pancreática bovina secuenciada 1963

Lisozima 1965 primera estructura de rayos X

Diferencias con reacciones catalizadas químicamenteAlta vel. De reacción 106-1012 más que no catalizadasCondiciones moderadas. Temp, pH, p atm.EspecificidadCapacidad de regulación

Ribozima

ENZIMAS: COMPOSICIÓN

ENZIMAS: COMPOSICIÓN

Recommendations of the Nomenclature Committee of the International Union of Biochemistry and Molecular Biology on the Nomenclature and Classification of

Enzymes by the Reactions they Catalyse

http://www.chem.qmul.ac.uk/iubmb/enzyme/

NOMENCLATURA ENZIMATICA

List of Recommended Names for Enzymes The common names of all listed enzymes are listed below, along with their EC numbers. Where an enzyme has been deleted or transferred to another EC number, this information is also indicated. Each list is linked to either separate entries for each entry or to files with up to 50 enzymes in each file.

Common Names for:

List linked to:

EC 1.1 to EC 1.3 separate up to 50

EC 1.4 to EC 1.97 separate up to 50

EC 2.1 to EC 2.4.1 separate up to 50

EC 2.4.2 to EC 2.9 separate up to 50

EC 3.1 to EC 3.3 separate up to 50

EC 3.4 to EC 3.12 separate up to 50EC 4 separate up to 50EC 5 separate up to 50EC 6 separate up to 50

EC 1 Oxidoreductases EC 1.1 Acting on the CH-OH group of donors EC 1.1.1 With NAD+ or NADP+ as acceptor

EC 1.1.1.1 alcohol dehydrogenaseEC 1.1.1.2 alcohol dehydrogenase (NADP+)

EC 1.1.1.3 homoserine dehydrogenaseEC 1.1.1.4 (R,R)-butanediol dehydrogenaseEC 1.1.1.5 acetoin dehydrogenaseEC 1.1.1.6 glycerol dehydrogenaseEC 1.1.1.7 propanediol-phosphate dehydrogenaseEC 1.1.1.8 glycerol-3-phosphate dehydrogenase (NAD+)

EC 1.1.1.9 D-xylulose reductase

EC 1.1.1.10 L-xylulose reductase

EC 1.1.1.11 D-arabinitol 4-dehydrogenase

EC 1.1.1.12 L-arabinitol 4-dehydrogenase

EC 1.1.1.13 L-arabinitol 2-dehydrogenase

EC 1.1.2 With a cytochrome as acceptorEC 1.1.2.1 now EC 1.1.99.5EC 1.1.2.2 mannitol dehydrogenase (cytochrome)EC 1.1.2.3 L-lactate dehydrogenase (cytochrome)

EC 1.1.2.4 D-lactate dehydrogenase (cytochrome)

EC 1.1.2.5 D-lactate dehydrogenase (cytochrome c-553) EC 1.1.3 With oxygen as acceptor

EC 1.1.3.1 deleted, included in EC 1.1.3.15EC 1.1.3.2 now EC 1.13.12.4EC 1.1.3.3 malate oxidaseEC 1.1.3.4 glucose oxidaseEC 1.1.3.5 hexose oxidaseEC 1.1.3.6 cholesterol oxidaseEC 1.1.3.7 aryl-alcohol oxidaseEC 1.1.3.8 L-gulonolactone oxidase

EC 1.1.4

With a disulfide as acceptorEC 1.1.4.1 vitamin-K-epoxide reductase (warfarin-sensitive)EC 1.1.4.2 vitamin-K-epoxide reductase (warfarin-insensitive) EC 1.1.5 With a quinone or similar compound as acceptor

EC 1.1.5.1 deleted, see EC 1.1.99.18 EC 1.1.5.2 quinoprotein glucose dehydrogenase

EC 1.1.99

With other acceptorsEC 1.1.99.1 choline dehydrogenaseEC 1.1.99.2 2-hydroxyglutarate dehydrogenaseEC 1.1.99.3 gluconate 2-dehydrogenase (acceptor)EC 1.1.99.4 dehydrogluconate dehydrogenaseEC 1.1.99.5 glycerol-3-phosphate dehydrogenaseEC 1.1.99.6 D-2-hydroxy-acid dehydrogenase

EC 1.1.99.7 lactate—malate transhydrogenaseEC 1.1.99.8 alcohol dehydrogenase (acceptor)

EC 1.2 Acting on the aldehyde or oxo group of donors EC 1.2.1 With NAD+ or NADP+ as acceptor

EC 1.2.1.1 deleted, replaced by EC 1.1.1.284 and EC 4.4.1.22EC 1.2.1.2 formate dehydrogenaseEC 1.2.1.3 aldehyde dehydrogenase (NAD+)

EC 1.2.1.4 aldehyde dehydrogenase (NADP+)

EC 1.2.1.5 aldehyde dehydrogenase [NAD(P)+]

EC 1.2.1.6 deleted

EC 1.2.2

With a cytochrome as acceptorEC 1.2.2.1 formate dehydrogenase (cytochrome)EC 1.2.2.2 pyruvate dehydrogenase (cytochrome)EC 1.2.2.3 formate dehydrogenase (cytochrome-c-553)EC 1.2.2.4 carbon-monoxide dehydrogenase (cytochrome-b-561)

EC 1.2.4

With a disulfide as acceptorEC 1.2.4.1 pyruvate dehydrogenase (acetyl-transferring)EC 1.2.4.2 oxoglutarate dehydrogenase (succinyl-transferring)EC 1.2.4.3 deleted, included in EC 1.2.4.4EC 1.2.4.4 3-methyl-2-oxobutanoate dehydrogenase (2-methylpropanoyl-transferring)

EC 1.2.7

With an iron-sulfur protein as acceptorEC 1.2.7.1 pyruvate synthaseEC 1.2.7.2 2-oxobutyrate synthaseEC 1.2.7.3 2-oxoglutarate synthaseEC 1.2.7.4 carbon-monoxide dehydrogenase (ferredoxin)

EC 1.2.99

With other acceptorsEC 1.2.99.1 now EC 1.1.99.19EC 1.2.99.2 carbon-monoxide dehydrogenase (acceptor)EC 1.2.99.3 aldehyde dehydrogenase (pyrroloquinoline-quinone)EC 1.2.99.4 formaldehyde dismutase

EC 1.3 Acting on the CH-CH group of donors EC 1.3.1 With NAD+ or NADP+ as acceptor

EC 1.3.1.1 dihydrouracil dehydrogenase (NAD+)

EC 1.3.1.2 dihydropyrimidine dehydrogenase (NADP+)

EC 1.3.1.3 4-3-oxosteroid 5-reductaseEC 1.3.1.4 cortisone -reductaseEC 1.3.1.5 cucurbitacin 23-reductase

EC 1.3.1.6 fumarate reductase (NADH)

EC 1.3.5

With a quinone or related compound as acceptorEC 1.3.5.1 succinate dehydrogenase (ubiquinone)EC 1.3.7 With an iron-sulfur protein as acceptorEC 1.3.7.1 6-hydroxynicotinate reductase EC 1.3.7.2 15,16-dihydrobiliverdin:ferredoxin oxidoreductaseEC 1.3.7.3 phycoerythrobilin:ferredoxin oxidoreductaseEC 1.3.7.4 phytochromobilin:ferredoxin oxidoreductase

EC 1.3.99

With other acceptors EC 1.3.99.1 succinate dehydrogenaseEC 1.3.99.2 butyryl-CoA dehydrogenaseEC 1.3.99.3 acyl-CoA dehydrogenaseEC 1.3.99.4 3-oxosteroid 1-dehydrogenaseEC 1.3.99.5 3-oxo-5-steroid 4-dehydrogenaseEC 1.3.99.6 3-oxo-5-steroid 4-dehydrogenaseEC 1.3.99.7 glutaryl-CoA dehydrogenaseEC 1.3.99.8 2-furoyl-CoA dehydrogenaseEC 1.3.99.9 now EC 1.21.99.1

EC 1.1.1.1

Common name: alcohol dehydrogenase

Reaction: an alcohol + NAD+ = an aldehyde or ketone + NADH + H+

Other name(s): aldehyde reductase; ADH; alcohol dehydrogenase (NAD); aliphatic alcohol dehydrogenase; ethanol dehydrogenase; NAD-dependent alcohol dehydrogenase; NAD-specific aromatic alcohol dehydrogenase; NADH-alcohol dehydrogenase; NADH-aldehyde dehydrogenase; primary alcohol dehydrogenase; yeast alcohol dehydrogenase

Systematic name: alcohol:NAD+ oxidoreductase

Comments: A zinc protein. Acts on primary or secondary alcohols or hemi-acetals; the animal, but not the yeast, enzyme acts also on cyclic secondary alcohols.

QUIMOTRIPSINA: SITIO ACTIVO

Quimotrisina. Estructura

Dihidrofolato reductasa: Efecto de la coenzima

ENERGÍA DE ACTIVACIÓN. PODER CATALÍTICO

Estado de transición. Interacciones débiles E-S

Disminución de entropía – Mayor velocidad

Aminoácidos en catálisis ácido-base

CINÉTICA ENZIMÁTICA

Kcat. Nº de Recambio

Kcat/Km. Constante de Especificidad

Cambios en el sustrato afectan actividad de Quimotripsina

Reacciones con 2 sustratos: Mecanismos

EFECTO DEL pH

ENZIMAS REGULADORAS: ALOSTERICAS

Transcarbamiolasa. Enzima alostérica

RETROINHIBICIÓNFeed-back

Cinética de enzimas alostericas

Enzimas reguladoras: Modificadas covalentemente

Glucógeno fosforilasa

GLUCÓGENO FOSFORILASA

Modificación covalente reversible