Enzymes Flashcards
(23 cards)
What is an enzyme?
Enzymes are proteins that acts as biological catalysts that exhibit a high degree of specifity
What’s a catalyst
any chemical that can speed up a chemical reaction without itself being changed
Give 2 characteristics of a catalyst
lowers AE
provides a faster reaction pathway
what are catalysts usually in
equilibrium
Give an example of a catalyst
cis to trans including a transition state
What enzyme catalyses this reaction
cis-trans isomerases
What are the 5 factors involved in enzyme catalysis
enzyme provides reaction surface and a suitable environment
enzyme brings reactants together - TS
it weakens bonds in reactions
and may participate in the reaction
True or false : enzymes form stronger reactions with the TS than with the substrate/product
true
Give the 3 stages of enzyme catalysis
1- ES complex
2- EP complex with a TS between
3- Enzyme and product separate
Give an advantage to induced fit model
flexible shape adjusts to the active site
ES-complex
enzyme intermediate
Active site
provides specific environment so reaction can occur quicker
Substrate
molecule bound to AS and acted upon by the enzyme
Define transition state
unstable high energy state structure of that of the reactant and product
How is the use of ATP used in enzymes reactions
to drive reaction in a certain direction
What does OH act as in an enzyme reaction
catalyst
Because OH is not a good catalyst what would make it better
needs boiling water
Diffusion controlled limit
rate at which molecules can get to the enzyme (10^9m-1s-1)
Cofactor
extral part of enzyme
Haloenzyme
active enzyme consisting of apoenzyme and coenzyme
What are the 3 factors affecting enzymes
Temperature,PH sub conc
cofactors and coenzymes
competitive and non-competitive inhibitors
Competitive inhibitor
structure of substrate and competes for active site
Non-competitive inhibitor
different shape and distorts enzyme shape and AS prevents binding
