Biotechnology and Biological Sciences Research Council (BBSRC)
BB/M011151/1
英国
Wellcome Trust
222373/Z/21/Z
英国
Wellcome Trust
105220/Z/14/Z
英国
Research Foundation - Flanders (FWO)
G0G0818N
ベルギー
Royal Society
RSRP/R1/211057
英国
引用
ジャーナル: Nat Commun / 年: 2021 タイトル: The role of membrane destabilisation and protein dynamics in BAM catalysed OMP folding. 著者: Paul White / Samuel F Haysom / Matthew G Iadanza / Anna J Higgins / Jonathan M Machin / James M Whitehouse / Jim E Horne / Bob Schiffrin / Charlotte Carpenter-Platt / Antonio N Calabrese / ...著者: Paul White / Samuel F Haysom / Matthew G Iadanza / Anna J Higgins / Jonathan M Machin / James M Whitehouse / Jim E Horne / Bob Schiffrin / Charlotte Carpenter-Platt / Antonio N Calabrese / Kelly M Storek / Steven T Rutherford / David J Brockwell / Neil A Ranson / Sheena E Radford / 要旨: The folding of β-barrel outer membrane proteins (OMPs) in Gram-negative bacteria is catalysed by the β-barrel assembly machinery (BAM). How lateral opening in the β-barrel of the major subunit ...The folding of β-barrel outer membrane proteins (OMPs) in Gram-negative bacteria is catalysed by the β-barrel assembly machinery (BAM). How lateral opening in the β-barrel of the major subunit BamA assists in OMP folding, and the contribution of membrane disruption to BAM catalysis remain unresolved. Here, we use an anti-BamA monoclonal antibody fragment (Fab1) and two disulphide-crosslinked BAM variants (lid-locked (LL), and POTRA-5-locked (P5L)) to dissect these roles. Despite being lethal in vivo, we show that all complexes catalyse folding in vitro, albeit less efficiently than wild-type BAM. CryoEM reveals that while Fab1 and BAM-P5L trap an open-barrel state, BAM-LL contains a mixture of closed and contorted, partially-open structures. Finally, all three complexes globally destabilise the lipid bilayer, while BamA does not, revealing that the BAM lipoproteins are required for this function. Together the results provide insights into the role of BAM structure and lipid dynamics in OMP folding.
Initial local fitting accomplished in Chimera. VMD was then used to setup cMDFF simulations that were run using NAMD. Both 7BNQ and 5LJO were used as initial models, with the best fitting parts of each then combined and flexibly fit again to generate the final conformation. This was then Real Space Refined in Phenix to generate the final structure
精密化
空間: REAL / プロトコル: FLEXIBLE FIT / 温度因子: 211
得られたモデル
PDB-7nbx: Lateral-open conformation of the lid-locked BAM complex (BamA E435C S665C, BamBDCE) by cryoEM