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Record 1,  Textual support,  English

Record number: 1, Textual support number: 1 DEF

First order rate constant that refers to the properties and reactions of the enzyme-substrate, enzyme-intermediate, and enzyme-product complexes.  1, record 1, English, - Kcat

Record number: 1, Textual support number: 1 CONT

Enzymes vary greatly in their rate enhancement ability, and not all have evolved to high maximum rate V_max of conversion. High enzyme efficiency, through lowering of activation energy, is dependent on the enzyme having a high ratio of K_cat/K_m, where K_cat is the rate constant for the reaction ... and K_m is the Michaelis constant (substrate concentration needed to give half maximum velocity).  3, record 1, English, - Kcat

Record number: 1, Textual support number: 1 OBS

In the simple Michaelis-Menten mechanism in which there is only one enzyme-substrate complex and all binding steps are fast, K_cat is simply the first-order rate constant for the chemical conversion of the ES complex to the EP complex. For more complicated reactions, K_cat is a function of all the first order rate constants, and it cannot be assigned to any particular process except when simplifying features occur.  1, record 1, English, - Kcat

Record number: 1, Textual support number: 2 OBS

The term Kcat should read K_cat.  4, record 1, English, - Kcat

Record 1,  Textual support,  French

Record number: 1, Textual support number: 1 DEF

Constante de premier ordre qui exprime le nombre de molécules de substrat transformées par molécule d'enzyme  1, record 1, French, - k%20catalytique

Record number: 1, Textual support number: 1 CONT

K_m définit bien l'affinité de l'enzyme pour son substrat. Cependant, si l'on observe plus en détail les relations (1) et (2) on constate que cette affinité dépend surtout des constantes k1 et k2. [...] À l'opposé la vitesse d'apparition des produits (P), donc en définitive la vitesse de réaction, dépend surtout de k3. C'est pourquoi on donne à cette constante K3 le nom de k catalytique ou^kcat. Selon la relation (3) on a : [...] k[indice]cat exprime donc le nombre de molécules de substrat transformées par molécules d'enzyme.  2, record 1, French, - k%20catalytique

Record number: 1, Textual support number: 1 OBS

En raison de contraintes d'ordre technique, les formules figurant dans la source CBT-167 ne peuvent être reproduites.  3, record 1, French, - k%20catalytique

Record number: 1, Textual support number: 2 OBS

Le terme Kcat s'écrit K_cat  3, record 1, French, - k%20catalytique

Record 1,  Textual support,  Spanish