TY - JOUR
T1 - Structural biology
T2 - Structures of aminoarabinose transferase ArnT suggest a molecular basis for lipid A glycosylation
AU - Petrou, Vasileios I.
AU - Herrera, Carmen M.
AU - Schultz, Kathryn M.
AU - Clarke, Oliver B.
AU - Vendome, Jérémie
AU - Tomasek, David
AU - Banerjee, Surajit
AU - Rajashankar, Kanagalaghatta R.
AU - Dufrisne, Meagan Belcher
AU - Kloss, Brian
AU - Kloppmann, Edda
AU - Rost, Burkhard
AU - Klug, Candice S.
AU - Trent, M. Stephen
AU - Shapiro, Lawrence
AU - Mancia, Filippo
N1 - Funding Information:
Crystallographic data for this study were collected at the Northeastern Collaborative Access Team beamlines 24ID-C and E, supported by National Institute of General Medical Sciences (NIGMS), NIH, grant P41 GM103403, at the Advanced Photon Source. The Pilatus 6M detector on 24-ID-C beam line is funded by an Office of Research Infrastructure High-End Instrumentation, NIH, grant S10 RR029205. This work was supported by an NIGMS initiative to the New York Consortium on Membrane Protein Structure (NYCOMPS; U54 GM095315) and by NIGMS grant R01 GM111980 (F.M.). Also acknowledged are NIH grants AI064184 and AI076322 (M.S.T.), and grant W911NF-12-1-0390 from the Army Research Office (M.S.T.). O.B.C. was supported by a Charles H. Revson Senior Fellowship. We thank W. Hendrickson for his leadership of NYCOMPS and continuous support and advice, A. Palmer and P. Loria for helpful discussions, and L. Hamberger for her assistance managing the Mancia laboratory. PDB accession codes: 5EZM (apo ArnTCm) and 5F15 (UndP-bound ArnTCm).
PY - 2016/2/5
Y1 - 2016/2/5
N2 - Polymyxins are antibiotics used in the last line of defense to combat multidrug-resistant infections by Gram-negative bacteria. Polymyxin resistance arises through charge modification of the bacterial outer membrane with the attachment of the cationic sugar 4-amino-4-deoxy-L-arabinose to lipid A, a reaction catalyzed by the integral membrane lipid-to-lipid glycosyltransferase 4-amino-4-deoxy-L-arabinose transferase (ArnT). Here, we report crystal structures of ArnT from Cupriavidus metallidurans, alone and in complex with the lipid carrier undecaprenyl phosphate, at 2.8 and 3.2 angstrom resolution, respectively. The structures show cavities for both lipidic substrates, which converge at the active site. A structural rearrangement occurs on undecaprenyl phosphate binding, which stabilizes the active site and likely allows lipid A binding. Functional mutagenesis experiments based on these structures suggest a mechanistic model for ArnT family enzymes.
AB - Polymyxins are antibiotics used in the last line of defense to combat multidrug-resistant infections by Gram-negative bacteria. Polymyxin resistance arises through charge modification of the bacterial outer membrane with the attachment of the cationic sugar 4-amino-4-deoxy-L-arabinose to lipid A, a reaction catalyzed by the integral membrane lipid-to-lipid glycosyltransferase 4-amino-4-deoxy-L-arabinose transferase (ArnT). Here, we report crystal structures of ArnT from Cupriavidus metallidurans, alone and in complex with the lipid carrier undecaprenyl phosphate, at 2.8 and 3.2 angstrom resolution, respectively. The structures show cavities for both lipidic substrates, which converge at the active site. A structural rearrangement occurs on undecaprenyl phosphate binding, which stabilizes the active site and likely allows lipid A binding. Functional mutagenesis experiments based on these structures suggest a mechanistic model for ArnT family enzymes.
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U2 - 10.1126/science.aad1172
DO - 10.1126/science.aad1172
M3 - Article
C2 - 26912703
AN - SCOPUS:84957545547
SN - 0036-8075
VL - 351
SP - 608
EP - 612
JO - Science
JF - Science
IS - 6273
ER -