Fluorescently labeled fusion protein for assaying adenosine triphosphate

摘要

The object of the present invention is to provide a substance, which is easy to handle and enables the measurement of ATP with a high sensitivity regardless of the concentration of protein, and further a measuring method of ATP using the substance. Such object is solved with a fluorescence labelled fusion protein obtained by attaching two types of fluorescent substances of potential donor and acceptor for fluorescence resonance energy transfer (FRET) respectively to a protein which can cause structural changes depending on ATP binding, namely epsilon protein, which is the subunit of ATP synthetase, and further solved by contacting the fluorescence labelled fusion protein with a subject substance and then measuring the fluorescence spectra.