. Author manuscript; available in PMC: 2010 May 19.

Published in final edited form as: Biochemistry. 2008 Jan 8;47(5):1414–1424. doi: 10.1021/bi701955e

Table 1.

Fluorescence Decay Parameters for the Single Trp TL Mutants with and without ANS^a

TL mutant	location	α₁	α₂	τ₁ (ns)	τ₂ (ns)	〈τ〉 (ns)	ET_τ (%)	ET_τ* (%)	ET_ss* (%)	χ²
E34W	loop AB	0.34	0.66	0.96	3.85	2.86				1.0
E34WANS		0.51	0.49	0.77	3.61	2.15	25	35	29	0.8
M39W	strand B	0.52	045	2.94	5.24	4.05				0.9
M39WANS		0.52	045	2.94	5.24	4.05	0	0	21	0.9
A66W	strand D	0.67	0.33	2.19	5.35	3.23				0.8
A66WANS		0.60	0.40	1.88	5.01	3.13	3	4	6	0.9
H84W	strand F	0.78	0.22	1.37	4.11	1.97				1.2
H84WANS		0.79	0.21	1.47	4.43	2.09	0	0	3	1.2
I88W	strand F	0.50	0.50	1.33	4.13	2.72				1.0
I88WANS		0.57	0.43	1.22	4.04	2.43	11	12	<0	1.1
F99W	strand G	0.79	0.21	1.77	5.22	2.49				1.0
F99WANS		0.71	0.29	1.84	4.73	2.68	0	0	8	1.1
C101W	strand G	0.54	0.46	1.84	4.93	3.27				1.0
C101WANS		0.65	0.35	1.80	6.32	3.04	7	7	18	0.9
L105W	strand G	0.73	0.27	1.04	3.81	1.77				1.2
L105WANS		0.89	0.11	0.64	3.68	0.97	46	52	64	1.0

Estimated errors for calculating ET efficiencies with steady-state and time-resolved fluorescence do not exceed 6%. An asterisk indicates the value was extrapolated to the ratio donor/acceptor = 1. ET_τ values were calculated from the time-resolved fluorescence measurements. ET_ss values were calculated from the steady-state fluorescence measurements.