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Selective Detection of Protein Homologues in Serum Using an OmpG Nanopore.

ABSTRACT: Outer membrane protein G is a monomeric ?-barrel porin that has seven flexible loops on its extracellular side. Conformational changes of these labile loops induce gating spikes in current recordings that we exploited as the prime sensing element for protein detection. The gating characteristics, open probability, frequency, and current decrease, provide rich information for analyte identification. Here, we show that two antibiotin antibodies each induced a distinct gating pattern, which allowed them to be readily detected and simultaneously discriminated by a single OmpG nanopore in the presence of fetal bovine serum. Our results demonstrate the feasibility of directly profiling proteins in real-world samples with minimal or no sample pretreatment.

SUBMITTER: Fahie MA

PROVIDER: S-EPMC5065927 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Selective Detection of Protein Homologues in Serum Using an OmpG Nanopore.

Fahie Monifa A MA Yang Bib B Mullis Martin M Holden Matthew A MA Chen Min M

Analytical chemistry 20151023 21

Outer membrane protein G is a monomeric β-barrel porin that has seven flexible loops on its extracellular side. Conformational changes of these labile loops induce gating spikes in current recordings that we exploited as the prime sensing element for protein detection. The gating characteristics, open probability, frequency, and current decrease, provide rich information for analyte identification. Here, we show that two antibiotin antibodies each induced a distinct gating pattern, which allowed ...[more]

PMID: 26451707

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