Figure 1
Time-resolved fluorescence decay curves of Peredox (0.1 μM) in the absence of NADH (a) and in the presence of 0.1 μM NADH (b). The decay curves (signal) were fitted by convoluting the IRF with a tri-exponential decay function as equation (1). The fractional amplitudes (α 1, α 2, α 3), lifetimes (τ 1, τ 2, τ 3) and goodness of fit (χ 2) are 26.8%, 41.8%, 31.4%, 3.1 ns, 1.3 ns, 0.18 ns, 1.11 for panel (a) and 60.4%, 17.1%, 22.5%, 3.2 ns, 1.2 ns, 0.16 ns, 1.09 for panel (b), respectively. The fluorescence was excited at 405 nm and detected at 515 nm. Figure (c) and (d) showed time-resolved fluorescence decay curves described by a tri-exponential decay function \({I}({t})={A}{\sum }_{{i}=1}^{3}{{\alpha }}_{i}{\exp }(-t{/}{{\tau }}_{i})+{B}\). The parameters used in panel (c) were obtained from Figure (a), and panel (d) from Figure (b). Thus, the panels (c) and (d) correspond to the fluorescence decay curves of Peredox in the absence and in the presence of NADH, respectively. (e) Schematic illustration of the variation of fluorescence lifetime (amplitude-weighted, τ) and ratio of fractional intensities (R) after NADH bind to Peredox.
