Interaction between proteinase K and stilbene 420: Occurrence of efficient FRET

Abstract

In the present work, we report a systematic investigation of the interaction of Proteinase K with stilbene 420 dye based on steady-state and time-resolved fluorescence measurements. Efficient Forster resonance energy transfer (FRET) was noted from reduction in the fluorescence intensity of Proteinase K and enhanced fluorescence intensity of Stilbene 420 dye. This clearly suggests that Proteinase K acts as efficient donor and Stilbene 420 dye as excellent acceptor. The FRET parameters such as Forster distance (Ro), Spectral overlap integral (J(λ)), intermolecular distance (r), FRET rate constant and efficiency (E) are determined experimentally.