Divide and Conquer: A Tailored Solid‐state NMR Approach to Study Large Membrane Protein Complexes. (7th July 2022)

• Record Type: Journal Article
• Authors: Xiang, ShengQi; Pinto, Cecilia; Baldus, Marc
• Is Part Of: Angewandte Chemie. Volume 134:Number 33(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-07-07
• Subjects: BAM Complex -- Isotopic Labelling -- Membrane Protein Complex -- NMR Spectroscopy -- Proton Detection; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202203319
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Membrane proteins are known to exert many essential biological functions by forming complexes in cell membranes. An example refers to the β‐barrel assembly machinery (BAM), a 200 kDa pentameric complex containing BAM proteins A–E that catalyzes the essential process of protein insertion into the outer membrane of gram‐negative bacteria. While progress has been made in capturing three‐dimensional structural snapshots of the BAM complex, the role of the lipoprotein BamC in the complex assembly in functional lipid bilayers has remained unclear. We have devised a component‐selective preparation scheme to directly study BamC as part of the entire BAM complex in lipid bilayers. Combination with proton‐detected solid‐state NMR methods allowed us to probe the structure, dynamics, and supramolecular topology of full‐length BamC embedded in the entire complex in lipid bilayers. Our approach may help decipher how individual proteins contribute to the dynamic formation and functioning of membrane protein complexes in membranes. Abstract : We describe a protein‐selective labelling approach that allowed us to probe a single lipoprotein (BamC) in the pentameric BAM membrane protein complex by proton‐detected solid‐state NMR. Our results generate novel insights into the supramolecular structure of the BAM complex and provide evidence that the three BamC domains exhibit different dynamic properties within the 200 kDa complex embedded in lipid bilayers.