BIOL 201 Lecture Notes - Lecture 22: Nucleophile, Reagent, Reaction Coordinate
Document Summary
Glutamine synthetase enzyme that catalyzes formation of amino acid glutamate to glutamine. Two problems with this reaction: reaction is not spontaneous, oxygen is a really bad leaving group (enzyme will facilitate reaction by giving it a good lg) Hypothetical reaction (no enzyme): products are less thermodynamically stable than reactants, mainly due to bad lg (thermodynamic barrier) The threshold energy required to drive the theoretical synthesis of glutamine under. Threshold energy : amount of energy needed to input into a reaction to make it go to products. Glutamine synthetase provides help for glutamine to react with nh 4 : couple this reaction with another reaction, to provide the energy required to make the overall g" negative. Lower the activation energy by replacing the bad" leaving group with a "good" one. By using atp in the reaction, the enzyme can solve both of it"s problems with the reaction. Help couple reaction with another reaction, enough energy to make overall g" negative.
