3T57
Activity and Crystal Structure of Arabidopsis UDP-N-acetylglucosamine acyltransferase
Summary for 3T57
| Entry DOI | 10.2210/pdb3t57/pdb |
| Descriptor | UDP-N-acetylglucosamine O-acyltransferase domain-containing protein (2 entities in total) |
| Functional Keywords | left-handed parallel beta helix, acyltransferase, lipid a biosynthesis, lipid synthesis, acylation, transferase |
| Biological source | Arabidopsis thaliana (mouse-ear cress, thale-cress) |
| Total number of polymer chains | 1 |
| Total formula weight | 33281.82 |
| Authors | Raetz, C.R.H.,Joo, S.H. (deposition date: 2011-07-26, release date: 2012-05-23, Last modification date: 2023-09-13) |
| Primary citation | Joo, S.H.,Chung, H.S.,Raetz, C.R.,Garrett, T.A. Activity and Crystal Structure of Arabidopsis thalianaUDP-N-Acetylglucosamine Acyltransferase. Biochemistry, 51:4322-4330, 2012 Cited by PubMed Abstract: The UDP-N-acetylglucosamine (UDP-GlcNAc) acyltransferase, encoded by lpxA, catalyzes the first step of lipid A biosynthesis in Gram-negative bacteria, the (R)-3-hydroxyacyl-ACP-dependent acylation of the 3-OH group of UDP-GlcNAc. Recently, we demonstrated that the Arabidopsis thaliana orthologs of six enzymes of the bacterial lipid A pathway produce lipid A precursors with structures similar to those of Escherichia coli lipid A precursors [Li, C., et al. (2011) Proc. Natl. Acad. Sci. U.S.A. 108, 11387-11392]. To build upon this finding, we have cloned, purified, and determined the crystal structure of the A. thaliana LpxA ortholog (AtLpxA) to 2.1 Å resolution. The overall structure of AtLpxA is very similar to that of E. coli LpxA (EcLpxA) with an α-helical-rich C-terminus and characteristic N-terminal left-handed parallel β-helix (LβH). All key catalytic and chain length-determining residues of EcLpxA are conserved in AtLpxA; however, AtLpxA has an additional coil and loop added to the LβH not seen in EcLpxA. Consistent with the similarities between the two structures, purified AtLpxA catalyzes the same reaction as EcLpxA. In addition, A. thaliana lpxA complements an E. coli mutant lacking the chromosomal lpxA and promotes the synthesis of lipid A in vivo similar to the lipid A produced in the presence of E. coli lpxA. This work shows that AtLpxA is a functional UDP-GlcNAc acyltransferase that is able to catalyze the same reaction as EcLpxA and supports the hypothesis that lipid A molecules are biosynthesized in Arabidopsis and other plants. PubMed: 22545860DOI: 10.1021/bi3002242 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.1 Å) |
Structure validation
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