Question

Cyanide as irreversible inhibitor:

1. Browsing certain websites showed me that CN^- is an irreversible inhibitor. If it binds to Mb, how will this affect the Km and Vmax?

2. If CN^- is irreversible, then is it considered as a competitive or non-competitive inhibitor or uncompetitive inhibitor?

3. Which one has high Km; CO or CN^- ?

Answer 1

11, 2) for competitive inhibitor, reaction may be fool reves reversible, for But non competitive inhibitor, reaction may be irreversible so , CN- is considered as non-competitive inhibitor , for non-competitive inhibition Ets ² ES EXP 4t K,= [E] [I] ESI [ET] BK = [ES] [] [ESI]

here, if k, = Kit for non competitive inhibits Vmax decreases and kom stays constant- -v maje tinhibitor) - rith non - competitive inhibitor without inhibitor - Vway Vway - km for Mb inhibitos co ligand has high km than CN 3) As in Mb inhibition takes place for Fe21 state. the binding constant for is much higher than CN because, as Herre has (-2) charge so, in intibition the overall charge of Mb will be o (neutral) for co binding. The binding constant of co kd value ~ 10% order) is higher. Co has higher km value