Ribose

Monosaccharide of 5 C atoms (pentose) with the molecular formula: C5H10O5. In contrast to glucose, ribose cannot be fermented by yeast. D-ribose is present in free form only to a small extent in the open form (see formula), but via hemiacetal formation (from C1- to C5) as pyranose (6-membered ring). Ribose can be synthesized in the human organism from other monosaccharides via the pentose phosphate cycle.

D-ribose (in contrast to L-ribose) plays an important role in nature, for example as a component of RNA (ribonucleic acid). The derivative of ribose, deoxyribose (hydroxy group on the 2nd carbon atom is missing), is an important component of DNA(deoxyribonucleic acid).

Ribose is a component of the most important biological energy source ATP (adenosine triphosphate)/ADP (adenosine diphosphate)/AMP (adenosine monophosphate) via adenosine. In the cells, the cyclic AMP (cAMP) plays a decisive role as secondary messenger. In the adenosine component of these molecules, ribose is linked to adenine via the C1 atom.