a (3R)-3-hydroxyacyl-[acyl-carrier protein] + UDP-2-acetamido-3-amino-2,3-dideoxy-alpha-D-glucopyranose = an [acyl-carrier protein] + a UDP-2-acetamido-2,3-dideoxy-3-{[(3R)-3-hydroxyacyl]amino}-alpha-D-glucopyranose [RN:R12931]
The enzyme is found in bacterial species whose lipid A contains 2,3-diamino-2,3-dideoxy-D-glucopyranose. Some enzymes, such as that from Leptospira interrogans, are highly specific for 2,3-diamino-2,3-dideoxy-D-glucopyranose, while others, such as the enzyme from Acidithiobacillus ferrooxidans, are also able to accept UDP-N-acetyl-alpha-D-glucosamine (cf. EC 2.3.1.129, acyl-[acyl-carrier-protein]---UDP-N-acetylglucosamine O-acyltransferase). The enzymes from different organisms also differ in their specificity for the acyl donor. The enzyme from Leptospira interrogans is highly specific for (3R)-3-hydroxydodecanoyl-[acp], while that from Mesorhizobium loti functions almost equally well with 10-, 12-, and 14-carbon 3-hydroxyacyl-[acp]s.
Enzymatic synthesis of lipid A molecules with four amide-linked acyl chains. LpxA acyltransferases selective for an analog of UDP-N-acetylglucosamine in which an amine replaces the 3"-hydroxyl group.