A cell wants to create compound E, but ∆G > 0 and breakdown of ATP does not release enough energy...?

A cell wants to create compound E, but the reaction A + B --> E has a ∆G = + 13.5 kcal/mol. Keep in mind that the breakdown of ATP only releases 7.3 kcal/mol of energy. What is one strategy that the cell could use in order to make compound E from A and B?