Biochemistry 153A: Week 9 Discussion
Bioenergetics and Glycolysis

Theme for the week:
There is a difference between thermodynamic and kinetic control.

Regulation of enzyme-catalyzed reactions
(p78, #15)
Indicate whether each of the following enzyme-catalyzed reactions would be more likely to be regulated (R) or unregulated (U).
a) DG close to zero. U No sense to waste on a reaction in equilibrium.
b) last step before a branch point. U Another waste.
c) highly spontaneous. R
d) first step after a branch point. R This is the case in many metabolic pathways
e) maximum catalysis required at all times. U Unnecessary
f) same reaction used in pathway making B from A and in pathway breaking down B to A. U Similar to an equilibrium reaction.

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