OmpA controls order in the outer membrane and shares the mechanical load

• 成果类型: Article
• 署名作者: Benn, Georgina; Borrelli, Carolina; Prakaash, Dheeraj; Johnson, Alex N. T.; Fideli, Vincent A.; Starr, Tahj; Fitzmaurice, Dylan; Combs, Ashton N.; Wuehr, Martin; Rojas, Enrique R.; Khalid, Syma; Hoogenboom, Bart W.; Silhavy, Thomas J.
• 署名单位: Princeton University; University of London; University College London; University of London; University College London; Imperial College London; University of Oxford; Princeton University; Princeton University; University of London; University College London; New York University
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-12752
• DOI: 10.1073/pnas.2416426121
• 发表日期: 2024-12-10
• 关键词: bacterial-cell wall; escherichia-coli; molecular-dynamics; protein; envelope; quantification; peptidoglycan; proteomics

摘要

OmpA, a predominant outer membrane (OM) protein in Escherichia coli, affects virulence, adhesion, and bacterial OM integrity. However, despite more than 50 y of research, the molecular basis for the role of OmpA has remained elusive. In this study, we demonstrate that OmpA organizes the OM protein lattice and mechanically connects it to the cell wall (CW). Using gene fusions, atomic force microscopy, simulations, and microfluidics, we show that the beta- barrel domain of OmpA is critical for maintaining the permeability barrier, but both the beta- barrel and CW-binding domains are necessary to enhance the cell envelope's strength. OmpA integrates the compressive properties of the OM protein lattice with the tensile strength of the CW, forming a mechanically robust composite that increases overall integrity.This coupling likely underpins the ability of the entire envelope to function as a cohesive, resilient structure, critical for the survival of bacteria.