enzymes Flashcards
biological catalyst that functions to speed up the rate of a biological reaction, but is not altered or consumed in the reaction
enzyme
energy needed for the reaction to go to completion
activation energy
the substances upon which an enzyme acts
substrates
the substances produced by chemical modification of substrates
products
the specific region on/in an enzyme where substrates bind and where the catalytic reaction occurs
active site
the unstable “energized” intermediate formed in an enzymatic reaction that has properties of both the substrate and the product
transition state
three things enzymes do to lower the activation energy
orienting/holding substrates very close together
creating/stabilizing the transition state intermediate
facilitating the reaction via reactive amino acids in the active site
the model that suggests the enzyme active site perfectly matches the shape of the substrate and so the enzyme allows only one substrate to bind to the active site
lock and key model
model that suggests substrates fit to active site like a flexible hand in glove, the enzyme-substrate binding changes the shape of both the enzyme and the substrate to fit snugly
induced fit model
catalyze oxidation-reduction reactions; add/remove electrons from its substrate
oxidoreductases
transfer a functional group from one molecule to another
transferases
cleave bonds by adding a water molecule
hydrolases
remove functional groups via non-hydrolytic reactions
lyases
catalyze rearrangements of functional groups within a molecule
isomerases
use the energy from ATP hydrolysis to form bonds between two substrate molecules
ligases
