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Antibody-induced oligomerization and activation of an engineered reporter enzyme.

ABSTRACT: Our objective is to produce a protein biosensor (or molecular switch) that is specifically activated in solution by a monoclonal antibody. Many effector-dependent enzymes have evolved in nature, but the introduction of a novel regulatory mechanism into a normally unregulated enzyme poses a difficult design problem. We used site-saturation mutagenesis and screening to generate effector-activated variants of the reporter enzyme beta-glucuronidase (GUS). The specific activity of the purified epitope-tagged GUS variant was increased by up to approximately 500-fold by the addition of an equimolar concentration of a monoclonal antibody. This molecular switch is modular in design, so it can easily be re-engineered for the detection of other peptide-specific antibodies. Such antibody-activated reporters could someday enable point-of-care serological assays for the rapid detection of infectious diseases.

SUBMITTER: Geddie ML

PROVIDER: S-EPMC1995550 | biostudies-literature | 2007 Jun

REPOSITORIES: biostudies-literature

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Antibody-induced oligomerization and activation of an engineered reporter enzyme.

Geddie Melissa L ML Matsumura Ichiro I

Journal of molecular biology 20070404 4

Our objective is to produce a protein biosensor (or molecular switch) that is specifically activated in solution by a monoclonal antibody. Many effector-dependent enzymes have evolved in nature, but the introduction of a novel regulatory mechanism into a normally unregulated enzyme poses a difficult design problem. We used site-saturation mutagenesis and screening to generate effector-activated variants of the reporter enzyme beta-glucuronidase (GUS). The specific activity of the purified epitop ...[more]

PMID: 17467736

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