Ubiquinones
Ubiquinones are organic compounds that are common in all living things (Latin ubique = everywhere) and function as electron and proton carriers in the respiratory chain . Ubiquinone-10 is mainly active in humans .
Base body of ubiquinones is the substance group of quinones scoring 1,4-benzoquinone which in positions 2 and 3 is a methoxy group in the 6-position, a methyl group and in position 5 an isoprenoid containing side chain. The ubiquinones are referred to as ubiquinone-1, ubiquinone-2, ubiquinone-3, etc. according to the number of isoprene units (n) in the side chain and are abbreviated as Q-1, Q-2, Q-3, etc.
Occurrence
Q-6 is found in the yeast Saccharomyces cerevisiae , in the bacterium Escherichia coli Q-8, in rodents Q-9 and in most other mammals, including humans, Q-10 predominates.