TABLE 1.

Lifetimes of various forms of membrane-bound gramicidin

Gramicidin conformation	α1	τ1 (ns)	α2	τ2 (ns)	〈τ〉* (ns)
Nonchannel	0.78	1.05	0.22	4.25	2.76
Intermediate I	0.87	0.65	0.13	3.73	2.07
Intermediate II	0.83	0.64	0.17	2.92	1.74
Channel	0.89	0.87	0.11	3.46	1.72

The excitation wavelength was 297 nm; emission was monitored at 340 nm. All other conditions are as in Fig. 1. See Materials and Methods for other details.

^*Calculated using Eq. 5.