BIOC12H3 : lec08.docx
19 Oct 2013
School
Department
Course
Professor
Document Summary
Lec08 mechanisms of enzyme action: midterm covers lecture 5 to 8 speed of different reactions, reactions catalyzed by enzymes late for this slide. The y intercept is the vmax: competitive: km is lowered? (actually raised) (because substrate competing with inhibitor for enzyme), but vmax isn"t (if concentration of substrate is high enough, inhibitor won"t matter). Thus, x intercept moves, y intercept doesn"t: non-competitive: km doesn"t change, because the inhibitor doesn"t affect how quickly it binds. Vmax lowers, because inhibitor prevents the inhibitor from being freed up, and which lowers vmax. In reality we have multiple substrate interactions: substrate and co-substrates like atp, michaelis theory does not account for multi substrate interactions. Enzyme inhibitors: enzymes are inhibited by chemicals naturally, e. g. antibiotic penicillin, inhibits peptidases of peptidoglycans, because enzymes cannot recognize the substrates, drugs work by inhibition to prevent proteins or enzymes from functions.
