Marine Bacterial Sialyltransferases

Abstract

Sialyltransferases transfer N-acetylneuraminic acid (Neu5Ac) from the common donor substrate of these enzymes, cytidine 5′-monophospho-N-acetylneuraminic acid (CMP-Neu5Ac), to acceptor substrates. The enzymatic reaction products including sialyl-glycoproteins, sialyl-glycolipids and sialyl-oligosaccharides are important molecules in various biological and physiological processes, such as cell-cell recognition, cancer metastasis, and virus infection. Thus, sialyltransferases are thought to be important enzymes in the field of glycobiology. To date, many sialyltransferases and the genes encoding them have been obtained from various sources including mammalian, bacterial and viral sources. During the course of our research, we have detected over 20 bacteria that produce sialyltransferases. Many of the bacteria we isolated from marine environments are classified in the genus Photobacterium or the closely related genus Vibrio. The paper reviews the sialyltransferases obtained mainly from marine bacteria.

“Lost sugars” — reality of their biological and medical applications

“…These enzymes catalyse the transfer of Sia (Neu5Ac or another derivative of sialic acid) from its activated sugar nucleotide donor, CMP-sialic acid, to an acceptor [90]. They govern addition of Sia with α-2,3-or α-2,6-linkage to the terminal galactose, with α-2,6-linkage to the terminal GalNAc or with α-2,8-linkage to the terminal Sias [99].…”

Purification of Marine Bacterial Sialyltransferases and Sialyloligosaccharides

“…To date, many sialyltransferases, and the genes encoding them, have been isolated from various sources including mammalian, bacterial, and viral sources (Schauer, 2004;Sujino et al, 2000;Yamamoto et al, 2006). During our research, we have isolated over 20 bacteria that produce sialyltransferase and have revealed the characteristics of these enzymes (Kajiwara et al, 2009;Yamamoto, 2010). In this chapter, we will introduce our research activities focusing on methods for (1) screening bacteria for glycosyltransferase activity; (2) purifying native sialyltransferases from marine bacteria; and (3) synthesizing and purifying sialyloligosaccharides produced by marine bacterial sialyltransferases.…”

Diversity, Abundance and Distribution of O-linked Glycosylation Pathway Enzymes in Prokaryotes-A Comparative Genomics Study

“…GTs are potential drug targets (see, for example, [9]). In addition, their promiscuous substrate specificity in response to variations in the assay conditions is advantageous for in vitro glycan synthesis [23,24]. Experimental approaches for the identification of new GTs include the use of probes derived from the sequences of hitherto characterized GTs [25] and screening cell lysates for activity [26].…”