A-ATP Synthase
From Proteopedia
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Active/Alternating Catalytic Model
The active site of B subunit is cycling between 3 states. 5 STEPS- ONE IS STANSITION STATE the deviations between the three states are concentrated within three regions… As "Open state"-ADP and Pi enter active site
(P loop farthers, s238 farthest)
Avi "loose state"-closes up around molecules and binds them loosely (transition state has more free energy than both S and P)
(P loop intermediate S238 closest G234 residue sidechain k240 P loop closer)
Apnp "tight state"- forces molecules together, binding ATP with high affinity
(P loop closest S238 int K240 significant)
possible sources of error can be the fact that ADp is not bound during transition state? is synthase reversible? where is it located? absence of ADP, may not affect the formation of transition-like state because of example
reaction coordination=freeze frame picture of reactants*RELATE TO LECTURE
substrates=higher free energy than products
when the enzyme is complementary to the substrate, the E.S. complex is more stable, has less free energy in the ground state than substrate alone. You increase the activation energy.
Mutants
References
Proteopedia Page Contributors and Editors (what is this?)
Kaitlin Chase MacCulloch, Michal Harel, Alexander Berchansky
