Glycosyl transferase, family 19 (IPR003835)

Short name: Glyco_trans_19

Overlapping homologous superfamilies


Family relationships



The biosynthesis of disaccharides, oligosaccharides and polysaccharides involves the action of hundreds of different glycosyltransferases. These enzymes catalyse the transfer of sugar moieties from activated donor molecules to specific acceptor molecules, forming glycosidic bonds. A classification of glycosyltransferases using nucleotide diphospho-sugar, nucleotide monophospho-sugar and sugar phosphates (EC:2.4.1.-) and related proteins into distinct sequence based families has been described [PMID: 9334165]. This classification is available on the CAZy (CArbohydrate-Active EnZymes) web site. The same three-dimensional fold is expected to occur within each of the families. Because 3-D structures are better conserved than sequences, several of the families defined on the basis of sequence similarities may have similar 3-D structures and therefore form 'clans'.

These enzymes belong to the glycosyltransferase family 19 GT19. Lipid-A-disaccharide synthetase EC: is involved with acyl-[acyl-carrier-protein]--UDP-N-acetylglucosamine O-acyltransferase EC: and tetraacyldisaccharide 4'-kinase EC: in the biosynthesis of the phosphorylated glycolipid, lipid A, in the outer membrane of Escherichia coli and other bacteria. These enzymes catalyse the first disaccharide step in the synthesis of lipid-A-disaccharide.

GO terms

Biological Process

GO:0009245 lipid A biosynthetic process

Molecular Function

GO:0008915 lipid-A-disaccharide synthase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.