Enzyme Activity Regulation
- Enzyme concentration: linear increase in reaction velocity with increase in [E].
- Substrate Concentration: initial increase in velocity directly proportional to substrate concentration ultimately approaching maximum velocity
- Temperature: linear increase in velocity with increase in temperature to point where protein unfolds (denatures) then velocity falls dramatically. Temperature typically only considered in bacteria (consider thermophilic bacteria)
- pH: Each enzyme has a unique pH/velocity profile. Generally the maximum velocity coincides with the pH of the compartment in which the enzyme functions.
- Inhibitors
- Competitive inhibition: molecule mimics the structure of the natural substrate and competes for binding to the enzyme active site with substrate. Overcome by either increasing the substrate concentration or lowering the inhibitor concentration.
- Covalent poison: irreversible modification decreases effective concentration of enzyme.
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