Emili Lab
Babu Lab E.coli  cell envelope protein complexes

Global Landscape of Cell Envelope Protein Complexes in Escherichia coli

Babu. et al.

• Knowledge of cell envelope protein (CEP) complexes is vital for a mechanistic understanding of bacterial membrane assembly processes, antibiotic resistance and metabolic coordination, yet only limited characterization of relevant macromolecules has been reported to date. Here, we present a global proteomic survey of CEPs encompassing most of the inner- and outer-membrane and periplasmic proteins of Escherichia coli K-12. After extraction with non-denaturing detergents, we affinity-purified 785 endogenously-tagged CEPs and identified stably-associated polypeptides by precision mass spectrometry. The resulting high-quality physical interaction network, comprising most (77%) of all targeted CEPs, revealed many previously unknown heteromeric complexes. These include novel transporter systems and assemblies mediating membrane protein export/folding, outer membrane biogenesis, and multidrug export. We also establish unexpected mechanistic links coordinating nutrient uptake with microbial metabolism. The broad biological and evolutionary significance of this CEP ‘interactome’ provides insights into the functional landscape governing CE systems essential to bacterial growth and antibiotic resistance.


• From this website, you can access and download annotations, interactions, complexes, mass spectral evidence and probability scores and supplementary data for all E. coli cell envelope proteins analyzed in this study.