(a) Consider the following hypothetical metabolic pathway:

Under intracellular conditions, the activity of enzyme X is 100 pmol/106 cells/s. Calculate the effect on metabolic flux rate (pmol/106 cells/s) of B †’ C of the following treatments. Calculate as % change (increase or decrease).
Treatment% Change in flux
Inhibitor that reduces activity of X by 10%
Activator that increases activity of X by 10%
(b) Now consider a substrate cycle operating with enzymes X and Y in the same hypothetical metabolic pathway:

Under intracellular conditions, the activity of enzyme X is 100 pmol/106 cells/s, and that of enzyme Y is 80 pmol/106 cells/s. What are the direction and rate (pmol/106 cells/s) of metabolic flux between B and C?
(c) Calculate the effect on direction and metabolic flux rate of the following treatments. Calculate as % change (increase or decrease).

(d) Briefly summarizes the regulatory advantage(s) of a substrate cycle in a pathway.

Transcribed Image Text:

AB Direction offiux (B-C or C- freatment > B) % Change in flux Inhibitor thatreduces activity of X by 10% Actiyator that increases activity of X by 10% Doubling the activity of enzyme1