Effects of differences between cell-free and cell-associated glucosyltransferases fromLeuconostoc mesenteroideson gluco-oligosaccharides structure

Abstract

Summary The gluco-oligosaccharide structures depended largely upon the glucosyltransferase (GTF) differences. The oligosaccharides with four polymerisation degrees only was produced by Leuconostoc mesenteroides 6055L that contain more cell-free GTFs, while the gluco-oligosaccharides with two polymerisation degrees could be yielded by strains PC13 and L4 that have high cell-related GTFs. Also, more gluco-oligosaccharides with α-1, 6 glycosidic link as the backbone, accompanied by the α-1, 4 glycosidic link as a branch structure was formed in the presence of cell-free enzymes. The oligosaccharide with α-1, 3 glycosidic link that connects to all of other branch structures was observed in the presence of cell-related enzymes. To produce gluco-oligosaccharides with α-1, 3 glycosidic link, the L. mesenteroides strains with high proportion of cell-related GTFs should be recommended. This is the first time to discuss the effects of the differences between the cell-free and the cell-associated GTFs produced by L. mesenteroides on oligosaccharide structure.