Abstract: Sensors for detecting enzyme activity are provided. The sensors include substrate modules having environmentally sensitive labels and detection modules whose binding to the substrate modules results in changes in signals from the environmentally sensitive labels or polypeptides or polypeptide substrates including environmentally sensitive or fluorescent labels. Compositions including substrate modules, polypeptides, or polypeptide substrates and nucleic acids encoding enzymes and/or detection modules are also described. Methods of assaying enzyme activity using sensors including environmentally sensitive or fluorescent labels are provided, as are related methods for screening for modulators of enzyme activity.

Abstract: Sensors for detecting enzyme activity are provided. The sensors include substrate modules having environmentally sensitive labels and detection modules whose binding to the substrate modules results in changes in signals from the environmentally sensitive labels or polypeptides or polypeptide substrates including environmentally sensitive or fluorescent labels. Compositions including substrate modules, polypeptides, or polypeptide substrates and nucleic acids encoding enzymes and/or detection modules are also described. Methods of assaying enzyme activity using sensors including environmentally sensitive or fluorescent labels are provided, as are related methods for screening for modulators of enzyme activity.