enzymes dont affect the delta G, they only lower the activation energy. Therefore, the delta G stays the same

Delta G (written triangle G) = Delta H -T Delta S

Delta G (written triangle G) = Delta H -T Delta S

Delta G (written triangle G) = Delta H -T Delta S

When a chemical reaction has a negative delta G, the reaction is exothermic because delta G is the change in energy of a system and the change in its entropy. If the effect of a reaction is to reduce G, the process will be spontaneous so delta G is negative.

Hope this helps :)