Sialic acids (Sia) are a family of 9-carbon α-keto acid aminosugars found
predominantly at the non-reducing end of oligosaccharide chains on glycoproteins and
glycolipids. Since their discovery in the late 1930s, and subsequent naming by Blix,
Gottschalk and Klenk (Nature. 1957; 179: 1088), Sia are now recognized as occurring
ubiquitously in nature (except plants), and being involved in numerous biologically
important processes. In particular, the growing awareness of the significance of Sia in
human health and disease has led to an increase in research into Sia chemistry,
biochemistry and cell biology. In this chapter, the structure and occurrence of Sia will
be summarized, as well as aspects of Sia chemistry, biochemistry and cell biology not
covered in subsequent chapters of this eBook are also presented. Throughout this, and
subsequent chapters of this eBook the abbreviations and nomenclature summarised in
Schauer and Varki, (In Essentials of Glycobiology 2nd Ed, Cold Spring Harbor (NY):
Cold Spring Harbor Laboratory Press; 2009) will be used. Importantly, wherever
appropriate the reader will be directed to the relevant chapters of this eBook, or
extensive reviews for further detail.
Keywords: Sialic acid, sialobiology, sialylation, O-acetylation, sialic acid
structure, sialic acid occurrence, sialic acid biosynthesis, sialic acid function.
