Abstract

Sialic acids (Sia) represent a family of nine-carbon keto-sugars with an unusual high structural diversity. However, all members are biosynthetic derivatives of either N-acetylneuraminic acid or 2-keto-3-deoxy-D-glycero-D-galacto-nononic acid. In this chapter, we describe the biosynthesis of these two Sia precursors in vertebrates with a focus on the characteristiscs of the involved enzymes. In addition, the activation of the sugars as well as the degradation is included. Furthermore, dieseases and mouse models associated to the Sia biosynthesis pathway as well as biomedical implications are addressed.