Vitamin B5 is also known as pantothenic acid. Pantothenic means "everywhere", reflecting the fact that it proved difficult to discover a food item that did not contain it.
Like many acids, it is likely to be converted into a salt. It is often found as calcium pantothenate.
Pantothenic acid is used in the synthesis of coenzyme A which is used to bring pairs of carbon atoms
into the Krebs cycle, and to pass on a 4-carbon compound
within the cycle.
Coenzyme A is also important in the synthesis of lipids, and by acylation/acetylation
in enzyme activation/deactivation, and in signal transduction.