Status of Sialic Acids and Their Role on Pseudomonas Aeruginosa in Host-Pathogen Interaction

Abstract

“Sialic acids are not only the most interesting molecules in the world, but also the most important”, said by Eric Sixmister set the exhilarating theme of the field of sialoglycobiology and challenges encountered by glycobiologists working with this molecule (Vimr, 1994). Sialic acids (Sias) are nine carbon acidic sugars typically found as the terminal residue of cell surface sugar chains as well as on secreted glycoproteins and in the extracellular matrix (Varki et al.,2009). The monosaccharide sialic acid is metabolically derived from two „primary‟ Sias; Nacetylneuraminic acid and 2-keto-3- deoxynomonic acid. N-acetylneuraminic acid(Neu5Ac) is the most common sialic acid in humans. The molecular structure is shown in Figure 1-1. In other mammals Nglycolylneuraminic acid (Neu5Gc) which is resulted due to hydroxylation of Neu5Ac, is also abundant. The enzyme that mediates the hydroxylation reaction contains a specific mutation in humans, which results in the lack of Neu5Gc in normal healthy individuals