A left-handed parallel beta helix in the structure of UDP-N-acetylglucosamine acyltransferase.
UDP-N-acetylglucosamine 3-O-acyltransferase (LpxA) catalyzes the transfer of (R)-3-hydroxymyristic acid from its acyl carrier protein thioester to UDP-N-acetylglucosamine. LpxA is the first enzyme in the lipid A biosynthetic pathway and is a target for the design of antibiotics. The x-ray crystal structure of LpxA has been determined to 2.6 angstrom resolution and reveals a domain motif composed of parallel beta strands, termed a left-handed parallel beta helix (L beta H). This unusual fold displays repeated violations of the protein folding constraint requiring right-handed crossover connections between strands of parallel beta sheets and may be present in other enzymes that share amino acid sequence homology to the repeated hexapeptide motif of LpxA.
D000217:Acyltransferases / Q000737:chemistry*; D000595:Amino Acid Sequence; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D017510:Protein Folding; D017433:Protein Structure, Secondary; D016415:Sequence Alignment
D000217:Acyltransferases; C050304:acyl-(acyl-carrier-protein)-UDP-N-acetylglucosamine acyltransferase