The $\Delta$ G $\degree$ ^' of the Conversion from Malate to Oxaloacetate in Malate

Essay

The $\Delta$ G $\degree$ ^' of the conversion from malate to oxaloacetate in the last reaction of the citrate cycle is very large, indicating this reaction is not thermodynamically favorable. Propose an explanation for how this reaction can proceed in the forward direction despite the very positive $\Delta$ G $\degree$ ^' value.