Ultrasensitive detection of protein translocated through toxin pores in droplet-interface bilayers
- 26 September 2011
- journal article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 108 (40), 16577-16581
- https://doi.org/10.1073/pnas.1113074108
Abstract
Many bacterial toxins form proteinaceous pores that facilitate the translocation of soluble effector proteins across cellular membranes. With anthrax toxin this process may be monitored in real time by electrophysiology, where fluctuations in ionic current through these pores inserted in model membranes are used to infer the translocation of individual protein molecules. However, detecting the minute quantities of translocated proteins has been a challenge. Here, we describe use of the droplet-interface bilayer system to follow the movement of proteins across a model membrane separating two submicroliter aqueous droplets. We report the capture and subsequent direct detection of as few as 100 protein molecules that have translocated through anthrax toxin pores. The droplet-interface bilayer system offers new avenues of approach to the study of protein translocation.Keywords
This publication has 33 references indexed in Scilit:
- Chemical Dissection of Protein Translocation through the Anthrax Toxin PoreAngewandte Chemie-International Edition, 2011
- Interactions of anthrax lethal factor with protective antigen defined by site-directed spin labelingProceedings of the National Academy of Sciences, 2011
- Structural basis for the unfolding of anthrax lethal factor by protective antigen oligomersNature Structural & Molecular Biology, 2010
- Role of the Protective Antigen Octamer in the Molecular Mechanism of Anthrax Lethal Toxin Stabilization in PlasmaJournal of Molecular Biology, 2010
- A Semisynthesis Platform for Investigating Structure−Function Relationships in the N-Terminal Domain of the Anthrax Lethal FactorACS Chemical Biology, 2010
- Lethal factor unfolding is the most force-dependent step of anthrax toxin translocationProceedings of the National Academy of Sciences, 2009
- The Protective Antigen Component of Anthrax Toxin Forms Functional Octameric ComplexesJournal of Molecular Biology, 2009
- An approach to characterizing single‐subunit mutations in multimeric prepores and pores of anthrax protective antigenProtein Science, 2008
- COPI coatomer complex proteins facilitate the translocation of anthrax lethal factor across vesicular membranes in vitroProceedings of the National Academy of Sciences, 2008
- Phenylalanine-427 of anthrax protective antigen functions in both pore formation and protein translocationProceedings of the National Academy of Sciences, 2008