Ubiquinones are a series of homologous molecules that possess a quinone active center and an unsaturated fatty tail. Ubiquinones are so named because they are widely distributed (i.e. ubiquitous) in nature and throughout the human body. Structurally they are very similar to the menaquinones, like vitamin K2. The quinone group is like a courier for protons and electrons, which is the critical property that allows ubiquinones to act as antioxidants and as important intermediates in energy generation. The fatty tail is composed of isoprenoid subunits, which are five carbon building blocks that help all living things biosynthesize critical components like immune modulators, essential oils and hormones. The number of isoprenoid units in the fatty tail is often denoted in the name of specific ubiquinones. For instance, ubiquinone-10 is made from ten isoprenoid units. Ubiquinone-10 (aka CoQ10, coenzyme Q10, Q) is more commonly referred to as just "ubiquinone." This is because it is the most prevalent ubiquinone in almost all mammals, including humans.
