National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
R00GM123228
米国
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
R35GM150831
米国
引用
ジャーナル: bioRxiv / 年: 2025 タイトル: Structural basis of undecaprenyl phosphate glycosylation leading to polymyxin resistance in Gram-negative bacteria. 著者: Khuram U Ashraf / Mariana Bunoro-Batista / T Bertie Ansell / Ankita Punetha / Stephannie Rosario-Garrido / Emre Firlar / Jason T Kaelber / Phillip J Stansfeld / Vasileios I Petrou / 要旨: In Gram-negative bacteria, the enzymatic modification of Lipid A with aminoarabinose (L-Ara4N) leads to resistance against polymyxin antibiotics and cationic antimicrobial peptides. ArnC, an integral ...In Gram-negative bacteria, the enzymatic modification of Lipid A with aminoarabinose (L-Ara4N) leads to resistance against polymyxin antibiotics and cationic antimicrobial peptides. ArnC, an integral membrane glycosyltransferase, attaches a formylated form of aminoarabinose to the lipid undecaprenyl phosphate, enabling its association with the bacterial inner membrane. Here, we present cryo-electron microscopy structures of ArnC from in and nucleotide-bound conformations. These structures reveal a conformational transition that takes place upon binding of the partial donor substrate. Using coarse-grained and atomistic simulations, we provide insights into substrate coordination before and during catalysis, and we propose a catalytic mechanism that may operate on all similar metal-dependent polyprenyl phosphate glycosyltransferases. The reported structures provide a new target for drug design aiming to combat polymyxin resistance.
凍結剤: ETHANE / チャンバー内湿度: 100 % / チャンバー内温度: 277.15 K / 装置: FEI VITROBOT MARK IV 詳細: 3 microliters of ArnC incorporated into nanodiscs was applied to a glow-discharged UltraAuFoil (1.2/1.3) 300 mesh grids (Quantifoil), blotted with filter paper for 3.5 s, and flash-frozen by ...詳細: 3 microliters of ArnC incorporated into nanodiscs was applied to a glow-discharged UltraAuFoil (1.2/1.3) 300 mesh grids (Quantifoil), blotted with filter paper for 3.5 s, and flash-frozen by plunging in liquid ethane cooled with liquid nitrogen. Grids were stored in liquid nitrogen..