BIO 201 Lecture Notes - Lecture 18: Competitive Inhibition, Zymogen, Enzyme

• School: University at Buffalo
• Department: Biological Sciences
• Course: BIO 201
• Professor: Lara Hutson

Document Summary

Mechanisms of regulation: competitive inhibition (mechanisms of feedback inhibition, allosteric regulation (^, covalent modification, zymogen activation (detrimental to the cell) Do(cid:374)"t use up all of this (cid:396)ea(cid:272)tio(cid:374), (cid:271)e(cid:272)ause this (cid:396)ea(cid:272)tio(cid:374) helps (cid:449)ith othe(cid:396) (cid:396)ea(cid:272)tio(cid:374)s. Every dot is a compound and every line is a chemical reaction. Inhibitor binds at active site, preventing substrate binding. Can be reversible (natural) or irreversible (toxins or drugs) Many chemical weapons and insecticides: irreversible competitive inhibition of acetylcholinesterase (ache) A molecule binds to a location on enzyme other than the active site. This leads to conformational change of active site. Can be activating or inhibitory (allosteric inhibition often called non-competitive inhibition) Activator molecule binds to allosteric site resulting in a conformational change in the active site that promotes substrate binding. Enzyme is active only in presence of activator. Allosteric inhibitor binds somewhere other than active site, causing a conformational change in active site that prevents substrate binding. Enzyme is active only win absence of inhibitor.