University:
York University
Course:
BIOL 2020 | Biochemistry
Academic year:

2023
Views:

52

Pages:

3
Author:

Nick T.

Enzymes Reaction Conditions Can change rate of enzyme reaction of reactions in certain amount of time Enzyme Activity Enzyme activity depends on: Concentrations of substrate & enzyme "most form" substrate enzyme complex more of them - more likely to come together Enzymes work best at body temp (37°C) Temperature max rate around body temp (37°C) At higher temp proteins start to denature At Low temp enzymes slow down Enzymes Enzyme Regulation pH Chemistry of human body changes continuously Enzymes must be able to: Speed up or slow down Turn reactions on or off Enzymes must be regulated Activation: Any process that initiates or increases the action of an enzyme Inhibition: Any process that slows down or stops the action of an enzyme Optimal pH depends on where enzyme normally functions Changing pH changes charge of acidic and basic amino acids in proteins Allosteric Control Single or multistep feedback control Inhibition Covalent Modification Genetic Control Enzymes Allosteric Control Regulation Multi step feed back Control Enzyme Regulation: Feedback Contro Feedback control: regulation of an enzyme's activity by the product of a reaction later in the pathway Regulates an entire reaction pathway Substance A enzyme enzyme 2 enzyme 3 The Product of the pathway slows down the first enzyme in the pathway (feedback inhibition) When amore D than necessary: D'causes enzyme 1 to slow down or stop -When NOT enough D. Not enough D to slow down enzyme 1, so enzyme 1 keeps going fast Allosteric enzymes have 2 main. Sites active Site Substrate binds reacts regulation or allesteric site where molecule (regulator) binds to affect enzyme activity Two types of regulators "Activater small nonprotein that binds to enzyme activates enzyme Inhibitor small nen-proton that binds to enzyme inhibits enzyme Inhibition reversible inhibitor can leave, restening enzyme function activity (good) irreversible inhibiter is permanently band to enzyme "Competitive inhibitor Competes with Substrate to bind to active site "nencompetitive inhibitor does not compete with Substrate instead binde to allosteric site Enzyme Populations enzymes exist in a population of identical enzyme melesules When an inhibitor molecule binds to 20 enzyme that one becomes inactive The degree of inhibition depends on # of inhibitors vs # of enzyme molecules The more inhibitors, the greater likelyhood of inhibiting the brological process Competitive inhibitors good drugs "Very specific 'few side effects