Mitochondrial matrix
The cytosolic, intermembrane space, compartment has a water content of 3.8 μl/mg protein, while the mitochondrial matrix 0.8 μl/mg protein. 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. 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.
Douglas C. Wallace
Wallace is a pioneer in the study of mitochondrial DNA. Wallace and his colleagues introduced human mitochondrial genetics into the field of molecular genetics. In 1975, for the first time ever, Wallace could associate a genetic disorder with the mitochondrial DNA region (resistance to chloramphenicol) and in 1990 he described a mitochondrial DNA mutation as the cause of a particular form of myoclonic epilepsy. He has been instrumental in the study of the mitochondrial genome and has developed new methods for the analysis of mitochondrial DNA.