In the mitochondrion, the matrix is the space within the inner membrane. The word "matrix" stems from the fact that this space is viscous, compared to the relatively aqueous cytoplasm. The mitochondrial matrix contains the mitochondria's DNA, ribosomes, soluble enzymes, small organic molecules, nucleotide cofactors, and inorganic ions.[1] The enzymes in the matrix facilitate reactions responsible for the production of ATP, such as the citric acid cycle, oxidative phosphorylation, oxidation of pyruvate, and the beta oxidation of fatty acids.[1]
The composition of the matrix based on its structures and contents produce an environment that allows the anabolic and catabolic pathways to proceed favorably for. The electron transport chain and enzymes in the matrix play a large role in the citric acid cycle and oxidative phosphorylation. The citric acid cycleproduces NADH and FADH2 through oxidation that will be reduced in oxidative phosphorylation to produce ATP.[2][3]
The cytosolic, intermembrane space, compartment has a water content of 3.8 μL/mg protein, while the mitochondrial matrix 0.8 μL/mg protein.[4] It is not known how mitochondria maintain osmotic balance across the inner mitochondrial membrane, although the membrane contains aquaporins that are believed to be conduits for regulated water transport. Mitochondrial matrix has a pH of about 7.8, which is higher than the pH of the intermembrane space of the mitochondria, which is around 7.0–7.4.[5] Mitochondrial DNA was discovered by Nash and Margit in 1963. One to many double stranded mainly circular DNA is present in mitochondrial matrix. Mitochondrial DNA is 1% of total DNA of a cell. It is rich in guanine and cytosine content. Mitochondria of mammals have 55s ribosomes.
https://en.wikipedia.org/wiki/Mitochondrial_matrix
A mitochondrion (/ˌmaɪtəˈkɒndriən/;[1] pl. mitochondria) is a double membrane-bound organelle found in most eukaryotic organisms. Mitochondria generate most of the cell's supply of adenosine triphosphate (ATP), used as a source of chemical energy.[2] Mitochondria were first discovered by Kolliker(1880 CE) in the voluntary muscles of insects. A mitochondrion is nicknamed the "powerhouse of the cell", first coined by Philip Siekevitz in a 1957 article of the same name.[3]
Some cells in some multicellular organisms lack mitochondria (for example, mature mammalian red blood cells). A large number of unicellular organisms, such as microsporidia, parabasalids, and diplomonads, have reduced or transformed their mitochondria into other structures.[4] One eukaryote, Monocercomonoides, is known to have completely lost its mitochondria,[5] and one multicellular organism, Henneguya salminicola, is known to have retained mitochondrion-related organelles in association with a complete loss of their mitochondrial genome.[5][6][7]
Mitochondria are commonly between 0.75 and 3 μm² in area[8] but they vary considerably in size and structure. Unless specifically stained, they are not visible. In addition to supplying cellular energy, mitochondria are involved in other tasks, such as signaling, cellular differentiation, and cell death, as well as maintaining control of the cell cycle and cell growth.[9] Mitochondrial biogenesis is in turn temporally coordinated with these cellular processes.[10][11] Mitochondria have been implicated in several human diseases and conditions, such as mitochondrial disorders,[12] cardiac dysfunction,[13] heart failure[14] and autism.[15]
The number of mitochondria in a cell can vary widely by organism, tissue, and cell type. A mature red blood cell has no mitochondria,[16] whereas a liver cell can have more than 2000.[17][18] The mitochondrion is composed of compartments that carry out specialized functions. These compartments or regions include the outer membrane, intermembrane space, inner membrane, cristae and matrix.
Although most of a cell's DNA is contained in the cell nucleus, the mitochondrion has its own genome ("mitogenome") that is substantially similar to bacterialgenomes.[19] Mitochondrial proteins (proteins transcribed from mitochondrial DNA) vary depending on the tissue and the species. In humans, 615 distinct types of proteins have been identified from cardiac mitochondria,[20] whereas in rats, 940 proteins have been reported.[21] The mitochondrial proteome is thought to be dynamically regulated.[22]
https://en.wikipedia.org/wiki/Mitochondrion
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