ribose, five-carbon sugar found in RNA (ribonucleic acid), where it alternates with phosphate groups to form the “backbone” of the RNA polymer and binds to nitrogenous bases. The molecular formula of ribose is C5H10O5. Ribose plays a vital role in certain biological processes, particularly in forming the structure and influencing the function of nucleic acids.
Ribose can exist in either of two forms: linear, which is rare and unstable, or cyclic (furanose), which is the most common form occurring in biological systems. It also exists in any of eight stereoisomers, the only naturally occurring and biologically active one of which is d-ribose. Ribose has multiple functions, in addition to serving as part of the structural core of nucleotides and nucleic acids. For instance, it is a component of nucleotide coenzymes, such as the energy-carrying molecule adenosine triphosphate (ATP), and is utilized by microorganisms in the synthesis of the amino acid histidine. Cofactors such as nicotinamide adenine dinucleotide (NAD+) and flavin adenine dinucleotide (FAD), which are critical actors in biochemical reactions, also contain ribose.
Ribose is sold as a dietary supplement. Manufacturers claim that it supports energy production and accelerates muscle recovery. Although used primarily by athletes, ribose supplements may benefit individuals who are affected by conditions associated with reduced energy levels, such as chronic fatigue syndrome and fibromyalgia.