mannosyltransferases of glycosyltransferase family 4 and similar proteins. This family is most closely related to the GT1 family of glycosyltransferases. ORF704 in E. coli has been shown to be involved in the biosynthesis of O-specific mannose homopolysaccharides.
Glycosyl transferases group 1. Mutations in this domain of PIGA lead to disease (Paroxysmal Nocturnal haemoglobinuria). Members of this family transfer activated sugars to a variety of substrates, including glycogen, Fructose-6-phosphate and lipopolysaccharides. Members of this family transfer UDP, ADP, GDP or CMP linked sugars. The eukaryotic glycogen synthases may be distant members of this family.
glycosyltransferases MtfB, WbpX, and similar proteins. This family is most closely related to the GT4 family of glycosyltransferases. MtfB (mannosyltransferase B) in E. coli has been shown to direct the growth of the O9-specific polysaccharide chain. It transfers two mannoses into the position 3 of the previously synthesized polysaccharide.
Escherichia coli WbuB and similar proteins. This family is most closely related to the GT1 family of glycosyltransferases. WbuB in E. coli is involved in the biosynthesis of the O26 O-antigen. It has been proposed to function as an N-acetyl-L-fucosamine (L-FucNAc) transferase.