|Superclasses:||Reactions Classified By Conversion Type → Simple Reactions → Chemical Reactions → Protein-Modification Reactions|
|Reactions Classified By Substrate → Macromolecule Reactions → Protein-Reactions → Protein-Modification Reactions|
EC Number: 18.104.22.168
Enzymes and Genes:
UDP-3-O-(R-3-hydroxymyristoyl)-glucosamine N-acyltransferase : lpxD
In Pathway: lipid IVA biosynthesis
The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the Enzyme Commission system.
Most BioCyc compounds have been protonated to a reference pH value of 7.3, and some reactions have been computationally balanced for hydrogen by adding free protons. Please see the PGDB Concepts Guide for more information.
Mass balance status: Balanced.
Enzyme Commission Primary Name: UDP-3-O-(3-hydroxymyristoyl)glucosamine N-acyltransferase
Enzyme Commission Synonyms: UDP-3-O-acyl-glucosamine N-acyltransferase, UDP-3-O-(R-3-hydroxymyristoyl)-glucosamine N-acyltransferase, acyltransferase LpxD, acyl-ACP:UDP-3-O-(3-hydroxyacyl)-GlcN N-acyltransferase, firA (gene name), lpxD (gene name)
This is the third committed step in lipid A biosynthesis.
Enzyme Commission Summary:
The enzyme catalyzes a step of lipid A biosynthesis. LpxD from Escherichia prefers (R,S)-3-hydroxymyristoyl-[acyl-carrier protein] over (R,S)-3-hydroxypalmitoyl-[acyl-carrier protein] [Bartling09]. Escherichia coli lipid A acyltransferases do not have an absolute specificity for 14-carbon hydroxy fatty acids but can transfer fatty acids differing by one carbon unit if the fatty acid substrates are available. When grown on 1% propionic acid, lipid A also contains the odd-chain fatty acids tridecanoic acid, pentadecanoic acid, hydroxytridecanoic acid, and hydroxypentadecanoic acid [Bainbridge08]]|.
Bainbridge08: Bainbridge BW, Karimi-Naser L, Reife R, Blethen F, Ernst RK, Darveau RP (2008). "Acyl chain specificity of the acyltransferases LpxA and LpxD and substrate availability contribute to lipid A fatty acid heterogeneity in Porphyromonas gingivalis." J Bacteriol 190(13);4549-58. PMID: 18456814
Bartling09: Bartling CM, Raetz CR (2009). "Crystal structure and acyl chain selectivity of Escherichia coli LpxD, the N-acyltransferase of lipid A biosynthesis." Biochemistry 48(36);8672-83. PMID: 19655786
Buetow07: Buetow L, Smith TK, Dawson A, Fyffe S, Hunter WN (2007). "Structure and reactivity of LpxD, the N-acyltransferase of lipid A biosynthesis." Proc Natl Acad Sci U S A 104(11);4321-6. PMID: 17360522
Kelly93: Kelly TM, Stachula SA, Raetz CR, Anderson MS (1993). "The firA gene of Escherichia coli encodes UDP-3-O-(R-3-hydroxymyristoyl)-glucosamine N-acyltransferase. The third step of endotoxin biosynthesis." J Biol Chem 1993;268(26);19866-74. PMID: 8366125
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