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Ultrasensitive detection of protein translocated through toxin pores in droplet-interface bilayers.

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.

SUBMITTER: Fischer A

PROVIDER: S-EPMC3189069 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature

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Ultrasensitive detection of protein translocated through toxin pores in droplet-interface bilayers.

Fischer Audrey A Holden Matthew A MA Pentelute Brad L BL Collier R John RJ

Proceedings of the National Academy of Sciences of the United States of America 20110926 40

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-i ...[more]

PMID: 21949363

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