The peptidyl transferase activity of the ribosome does not require an additional source of free energy. Is the reaction catalyzed by glutamylcysteine synthetase (Problem 19) also exergonic?

Data from problem 19

Cells can make certain oligopeptides using conventional enzymes rather than mRNA-directed translation by a ribosome. Draw the product of the reaction catalyzed by L-glutamate: L-cysteine gamma-ligase (γ-glutamylcysteine synthetase).