Table III.

NBD fluorescence lifetimes of free and membrane-bound RNCs^a

NBD-labeled speciesb	Membranes	Probe-PTC separationc	NBD location	τ1	f1d	τ2	f2d	χ2	<τ>e
				ns		ns			ns
pPL90	+	15	Tunnel	0.7 ± 0.1	0.90	8.8 ± 0.2	0.10	4	1.5 ± 0.1
111p90	+	15	Tunnel	2.1 ± 0.2	0.61	8.6 ± 0.2	0.39	2	4.6 ± 0.2
111p130	+	55	Translocon	2.3 ± 0.4	0.61	7.9 ± 0.5	0.39	1	4.5 ± 0.4
111p130	−	55	Solvent	0.8 ± 0.1	0.75	9.2 ± 0.1	0.25	4	2.9 ± 0.1
2TML12K2122	+	18	Tunnel	2.5 ± 0.6	0.50	7.8 ± 0.3	0.50	3	5.2 ± 0.5
2TML12K2130	+	26	Tunnel	2.8 ± 0.1	0.61	9.4 ± 0.1	0.39	7	5.4 ± 0.1
2TML12K2148	+	44	Translocon	2.6 ± 0.2	0.55	9.5 ± 0.2	0.45	3	5.7 ± 0.2
2TML12K2160	+	56	Translocon	2.4 ± 0.3	0.54	9.3 ± 0.3	0.46	4	5.6 ± 0.3
2TML12K2180	−	76	Solvent	1.3 ± 0.3	0.65	8.0 ± 0.3	0.35	1	3.6 ± 0.3

^aFor each RTC, data from three or more independent experiments were combined and analyzed together as described in Materials and methods.

^bNBD is located at residue 104 of 2TM_L12K2 in these experiments.

^cNascent chain residues between nascent chain εNBD-Lys and the PTC.

^dMolar fraction.

^eAverage lifetime from molar fractions.