Single molecule reaction-diffusion with single photon FCS-FRET

Abstract

Here we propose a method that resolves chemical reactions at the single-molecule level from the fastest possible acquirable timescale, namely individual photon arrivals. We do so from the analysis of molecules as they traverse through an illuminated confocal spot and interact. A particular interest is the interaction of the intrinsically disordered protein fragments, including prothymosin α as well as its chaperone, histone H1.0. Our methods reveal the affinity of these fragments as they form larger ternary complexes with single-molecule resolution down to the millisecond timescale.