The mitochondrial matrix (mt-matrix) is enclosed by the mt-inner membrane mtIM. The terms mitochondrial matrix space or mitochondrial lumen are used synonymously. The mt-matrix contains the enzymes of the tricarboxylic acid cycle, fatty acid oxidation and a variety of enzymes that have cytosolic counterparts (e.g. glutamate dehydrogenase, malic enzyme). Metabolite concentrations, such as the concentrations of fuel substrates, adenylates (ATP, ADP, AMP) and redox systems (NADH), can be very different in the mt-matrix, the mt-intermembrane space, and the cytosol. The finestructure of the gel-like mt-matrix is subject of current research.
MitoPedia concepts: MiP concept