InterPro domain: IPR011004

This domain superfamily is characterised by trimeric LpxA-like enzymes that display a single-stranded left-handed beta-helix fold, composed of tandem repeats of a hexapeptide, as represented by the Bacterial transferase hexapeptide repeat, where the hexapeptide repeats correspond to individual strands. Many bacterial transferases contain this domain. The structures of several proteins with this domain have been determined, including UDP N-acetylglucosamine acyltransferase (LpxA, 2.3.1.129 ) from Escherichia coli, the first enzyme in the lipid A biosynthetic pathway [ 1 ]; galactoside acetyltransferase (GAT, LacA, 2.3.1.18 ) from E. coli, a gene product of the lac operon that may assist cellular detoxification [ 2 ]; gamma-class Archaeon carbonic anhydrase ( 4.2.1.1 ), a zinc-containing enzyme that catalyses the reversible hydration of carbon dioxide [ 3 ]; tetrahydrodipicolinate-N-succinlytransferase (DapD) from Mycobacterium bovis, an enzyme from the lysine biosynthetic pathway that contains an extra N-terminal 3-helical domain [ 4 ]; and the C-terminal domain of N-acetylglucosamine 1-phosphate uridyltransferase (GlmU, 2.7.7.23 ) from E. coli, a trimeric bifunctional enzyme that catalyses the last two sequential reactions in the de novo biosynthetic pathway for UDP-N-acetylglucosamine, an essential precursor for many biomolecules [ 5 ].

1. A left-handed parallel beta helix in the structure of UDP-N-acetylglucosamine acyltransferase. Science 270, 997-1000
2. Structure of the lac operon galactoside acetyltransferase. Structure 10, 581-8
3. A closer look at the active site of gamma-class carbonic anhydrases: high-resolution crystallographic studies of the carbonic anhydrase from Methanosarcina thermophila. Biochemistry 39, 9222-31
4. Acyl group specificity at the active site of tetrahydridipicolinate N-succinyltransferase. Protein Sci. 11, 974-9
5. Structure of the Escherichia coli GlmU pyrophosphorylase and acetyltransferase active sites. Biochemistry 40, 1913-21