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.
Thiamine monophosphate synthase (TMP synthase)/TenI. TMP synthase catalyzes an important step in the thiamine biosynthesis pathway, the substitution of the pyrophosphate of 2-methyl-4-amino-5- hydroxymethylpyrimidine pyrophosphate by 4-methyl-5- (beta-hydroxyethyl) thiazole phosphate to yield thiamine phosphate. TenI is a enzymatically inactive regulatory protein involved in the regulation of several extracellular enzymes. This superfamily also contains other enzymatically inactive proteins with unknown functions.