Possible enzyme activities leading to glutamate synthesis. 1, aconitase; 2, isocitrate dehydrogenase; 3, glutamate dehydrogenase; 4, succinyl-CoA synthetase; 5, αKG dehydrogenase; 6, aspartate:glutamate transaminase; 7, glutamate synthase; 8, glutamine synthetase. Metabolites include isocitrate (Ict) and succinyl-CoA (S-CoA).