IUBMB Enzyme Nomenclature


Accepted name: Kdo2-lipid A phosphoethanolamine 7''-transferase

Reaction: (1) diacylphosphatidylethanolamine + α-D-Kdo-(2→4)-α-D-Kdo-(2→6)-lipid A = diacylglycerol + 7-O-[2-aminoethoxy(hydroxy)phosphoryl]-α-D-Kdo-(2→4)-α-D-Kdo-(2→6)-lipid A
(2) diacylphosphatidylethanolamine + α-D-Kdo-(2→4)-α-D-Kdo-(2→6)-lipid IVA = diacylglycerol + 7-O-[2-aminoethoxy(hydroxy)phosphoryl]-α-D-Kdo-(2→4)-α-D-Kdo-(2→6)-lipid IVA

Glossary: lipid A = 2-deoxy-2-[(3R)-3-(tetradecanoyloxy)tetradecanamido]-3-O-[(3R)-3-(dodecanoyloxy)tetradecanoyl]-4-O-phospho-β-D-glucopyranosyl-(1→6)-2-deoxy-3-O-[(3R)-3-hydroxytetradecanoyl]-2-[(3R)-3-hydroxytetradecanamido]-α-D-glucopyranosyl phosphate
lipid IVA = 2-deoxy-2-[(3R)-3-hydroxytetradecanamido]-3-O-[(3R)-3-hydroxytetradecanoyl]-4-O-phospho-β-D-glucopyranosyl-(1→6)-2-deoxy-3-O-[(3R)-3-hydroxytetradecanoyl]-2-[(3R)-3-hydroxytetradecanamido]-α-D-glucopyranosyl phosphate

Other name(s): eptB (gene name)

Systematic name: diacylphosphatidylethanolamine:α-D-Kdo-(2→4)-α-D-Kdo-(2→6)-lipid-A 7''-phosphoethanolaminetransferase

Comments: The enzyme has been characterized from the bacterium Escherichia coli. It is activated by Ca2+ ions and is is silenced by the sRNA MgrR.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:


1. Kanipes, M.I., Lin, S., Cotter, R.J. and Raetz, C.R. Ca2+-induced phosphoethanolamine transfer to the outer 3-deoxy-D-manno-octulosonic acid moiety of Escherichia coli lipopolysaccharide. A novel membrane enzyme dependent upon phosphatidylethanolamine. J. Biol. Chem. 276 (2001) 1156-1163. [PMID: 11042192]

2. Reynolds, C.M., Kalb, S.R., Cotter, R.J. and Raetz, C.R. A phosphoethanolamine transferase specific for the outer 3-deoxy-D-manno-octulosonic acid residue of Escherichia coli lipopolysaccharide. Identification of the eptB gene and Ca2+ hypersensitivity of an eptB deletion mutant. J. Biol. Chem. 280 (2005) 21202-21211. [PMID: 15795227]

3. Moon, K., Six, D.A., Lee, H.J., Raetz, C.R. and Gottesman, S. Complex transcriptional and post-transcriptional regulation of an enzyme for lipopolysaccharide modification. Mol. Microbiol. 89 (2013) 52-64. [PMID: 23659637]

[EC created 2015]

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