Biochemical and molecular aspects of human mitochondrial respiratory chain disorders.

Functional mitochondrial respiratory chain and oxidative phosphorylation systems are obligate requirements for the normal function of most eukaryotic cells. When a defect of one of these systems occurs in humans, it results in a variety of clinical symptoms according to the severity of the defect and the tissues involved. Defects of all five multisubunit complcxes comprising the respiratory chain and oxidative phosphorylation systems have been reported [ 1-51, with some patterns emerging [ 61. but generally no clear picture correlating. the clinical symptoms and the biochemical or molecular