Ultrasensitive Detection of Protein Translocated Through Toxin Pores in Droplet-interface Bilayers

Overview

Journal Proc Natl Acad Sci U S A

Specialty Science

Date 2011 Sep 28

PMID 21949363

Citations 15

Authors

Audrey Fischer

Matthew A Holden

Brad L Pentelute

R John Collier

Affiliations

Soon will be listed here.

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.

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