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Selection of Protein-Protein Interactions of Desired Affinities with a Bandpass Circuit.

ABSTRACT: We have developed a genetic circuit in Escherichia coli that can be used to select for protein-protein interactions of different strengths by changing antibiotic concentrations in the media. The genetic circuit links protein-protein interaction strength to ?-lactamase activity while simultaneously imposing tuneable positive and negative selection pressure for ?-lactamase activity. Cells only survive if they express interacting proteins with affinities that fall within set high- and low-pass thresholds; i.e. the circuit therefore acts as a bandpass filter for protein-protein interactions. We show that the circuit can be used to recover protein-protein interactions of desired affinity from a mixed population with a range of affinities. The circuit can also be used to select for inhibitors of protein-protein interactions of defined strength.

SUBMITTER: Brechun KE

PROVIDER: S-EPMC6331253 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Selection of Protein-Protein Interactions of Desired Affinities with a Bandpass Circuit.

Brechun Katherine E KE Arndt Katja M KM Woolley G Andrew GA

Journal of molecular biology 20181115 2

We have developed a genetic circuit in Escherichia coli that can be used to select for protein-protein interactions of different strengths by changing antibiotic concentrations in the media. The genetic circuit links protein-protein interaction strength to β-lactamase activity while simultaneously imposing tuneable positive and negative selection pressure for β-lactamase activity. Cells only survive if they express interacting proteins with affinities that fall within set high- and low-pass thre ...[more]

PMID: 30448232

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