The following reaction coordinate diagram charts the energy of a substrate molecule (S) as it passes through a transition state (X^t) on its way to becoming a stable product (P) alone or in the presence of one of two different enzymes (El and E2). How does the addition of either enzyme affect the change in Gibb's free energy (ΔG) for the reaction? Which of the two enzymes binds with greater affinity to the substrate? Which enzyme better stabilizes the transition state? Which enzyme functions as a better catalyst?