Enzymes Flashcards
Enzymes
Protein catalysts that make chemical reactions speed up (substrate specific, bind to some things)
Activation Energy
energy required for reaction to occur
Substrate
substance enzyme works on
Active site
where substrates bind
lock and key
enzyme and substrate make this because they have unique fit
(specific enzyme for every reaction)
induced fit model
enzyme will change shape to fit substrate more effectively
Co factors
Non protein addition like iron or zinc
Co enzymes
Protein based vitamins improve substrate fit
Co enzymes and Co factors
both can bind at the active site or elsewhere on enzyme
pH
enzymes have a preferred pH for best function (some enzymes work best at acidic pH, like pepsin) (some enzymes work best at basic pH, like trypsin)
Temperature
as temp increases, rate of chemical reaction increases
substrate (or enzyme) concentration
enzyme reactions increase with increasing substrate concentration up to a certain point
competitive inhibitor
inhibitor blocks substrate from binding to active site (slows reaction)
non competitive inhibitor (allosteric activity)
compound that binds to enzyme in a site other than active site
changed shape of active site
substrate can’t fit anymore
slows reaction
Feedback inhibition
product of a reaction inhibits (stops) an enzyme earlier in sequence
brings entire process to a temporary halt
precursor activity
reactant is needed to activate an enzyme layer in metabolic pathway
brings entire process to temporary halt
negative feedback
negative feedback loops bring the system back to normal levels (homeostasis)
