NomenclatureNomenclature

ReactionsReactions

Substrates (reactants) -- A B C D Products -- P Q R S Enzyme -- E F G Inhibitors -- I J Activators

Metal ion -- Mn+/-

Other -- X Y Z

Substrates (reactants) -- A B C D Products -- P Q R S Enzyme -- E F G Inhibitors -- I J Activators

Metal ion -- Mn+/-

Other -- X Y Z

EnzymesEnzymes

Stable: when isolated from the rest of the reaction components, it has a long half-life with respect to the assay times scale, and reactants add to it in a bimolecular step.

Transitory: when isolated from the rest of the reaction components its half-life is short relative to the assay time scale.

Central: if the active site is completely filled and kinetically competent

Noncentral: if not.

Stable: when isolated from the rest of the reaction components, it has a long half-life with respect to the assay times scale, and reactants add to it in a bimolecular step.

Transitory: when isolated from the rest of the reaction components its half-life is short relative to the assay time scale.

Central: if the active site is completely filled and kinetically competent

Noncentral: if not.

Kinetic MechanismKinetic Mechanism

Sequential: all reactants must be bound to an enzyme before any reaction occurs.

Ping-Pong: a product is released between the addition of two substrates

Ordered: there is an obligatory order fo addition of reactants to an enzyme and /or release of products from enzyme.

Random: there is not.

Sequential: all reactants must be bound to an enzyme before any reaction occurs.

Ping-Pong: a product is released between the addition of two substrates

Ordered: there is an obligatory order fo addition of reactants to an enzyme and /or release of products from enzyme.

Random: there is not.

Kinetic ConstantsKinetic Constants

Michaelis constant (Km) is defined as the concentration of reactant that gives half the maximum rate at saturating concentrations of all other reactants and with products maintained at zero concentration.

Michaelis constant (Km) is defined as the concentration of reactant that gives half the maximum rate at saturating concentrations of all other reactants and with products maintained at zero concentration.

Rate ConstantsRate Constants

Microscopic: associated rate constants of the individual steps in a reaction scheme

First-order Second-order Macroscopic:

Microscopic: associated rate constants of the individual steps in a reaction scheme

First-order Second-order Macroscopic:

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Michaelis-MentenMichaelis-Menten

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