Editing Mitochondrial matrix (section)

=== Citric acid cycle ===
Following glycolysis, the citric acid cycle is activated by the production of acetyl-CoA. The oxidation of [[Pyruvic acid|pyruvate]] by pyruvate dehydrogenase in the matrix produces CO<sub>2</sub>, acetyl-CoA, and NADH. [[Beta oxidation]] of fatty acids serves as an alternate [[Catabolism|catabolic]] pathway that produces acetyl-CoA, NADH, and [[Flavin adenine dinucleotide|FADH<sub>2</sub>]].<ref name=":0" /> The production of acetyl-CoA begins the citric acid cycle while the [[Cofactor (biochemistry)|co-enzymes]] produced are used in the [[electron transport chain]].<ref name=":3" />[[File:Mitochondrial electron transport chain—Etc4.svg|thumb|ATP synthesis as seen from the perspective of the matrix. Conditions produced by the relationships between the catabolic pathways (citric acid cycle and oxidative phosphorylation) and structural makeup (lipid bilayer and electron transport chain) of matrix facilitate ATP synthesis.]]
All of the [[enzyme]]s for the citric acid cycle are in the matrix (e.g. ''[[Citrate|citrate synthase]], [[isocitrate dehydrogenase]], [[Alpha-Ketoglutaric acid|α-ketoglutarate dehydrogenase]], [[Fumarate|fumarase]], and [[malate dehydrogenase]]'') except for [[succinate dehydrogenase]] which is on the inner membrane and is part of protein [[complex II]] in the [[electron transport chain]]. The cycle produces coenzymes NADH and FADH<sub>2</sub> through the oxidation of carbons in two cycles. The oxidation of NADH and FADH<sub>2</sub> produces GTP from succinyl-CoA synthetase.<ref name=":1" />