ジャーナル: Sci Adv / 年: 2020 タイトル: Structural insight into the ATP-driven exporter of virulent peptide toxins. 著者: N Zeytuni / S W Dickey / J Hu / H T Chou / L J Worrall / J A N Alexander / M L Carlson / M Nosella / F Duong / Z Yu / M Otto / N C J Strynadka / 要旨: is a major human pathogen that has acquired alarming broad-spectrum antibiotic resistance. One group of secreted toxins with key roles during infection is the phenol-soluble modulins (PSMs). PSMs ... is a major human pathogen that has acquired alarming broad-spectrum antibiotic resistance. One group of secreted toxins with key roles during infection is the phenol-soluble modulins (PSMs). PSMs are amphipathic, membrane-destructive cytolytic peptides that are exported to the host-cell environment by a designated adenosine 5'-triphosphate (ATP)-binding cassette (ABC) transporter, the PSM transporter (PmtABCD). Here, we demonstrate that the minimal Pmt unit necessary for PSM export is PmtCD and provide its first atomic characterization by single-particle cryo-EM and x-ray crystallography. We have captured the transporter in the ATP-bound state at near atomic resolution, revealing a type II ABC exporter fold, with an additional cytosolic domain. Comparison to a lower-resolution nucleotide-free map displaying an "open" conformation and putative hydrophobic inner chamber of a size able to accommodate the binding of two PSM peptides provides mechanistic insight and sets the foundation for therapeutic design.
解像度: 1.4→40.46 Å / Cor.coef. Fo:Fc: 0.974 / Cor.coef. Fo:Fc free: 0.965 / WRfactor Rfree: 0.2086 / WRfactor Rwork: 0.1699 / FOM work R set: 0.8736 / SU B: 0.992 / SU ML: 0.039 / SU R Cruickshank DPI: 0.0598 / SU Rfree: 0.0639 / 交差検証法: THROUGHOUT / σ(F): 0 / ESU R: 0.06 / ESU R Free: 0.064 / 立体化学のターゲット値: MAXIMUM LIKELIHOOD 詳細: HYDROGENS HAVE BEEN ADDED IN THE RIDING POSITIONS U VALUES : REFINED INDIVIDUALLY
Rfactor
反射数
%反射
Selection details
Rfree
0.1937
1378
5.1 %
RANDOM
Rwork
0.1609
-
-
-
obs
0.1625
25672
98.39 %
-
溶媒の処理
イオンプローブ半径: 0.8 Å / 減衰半径: 0.8 Å / VDWプローブ半径: 1.2 Å / 溶媒モデル: MASK