Table 2. Crystallographic and calculated distances.

Comparison between the monomer–monomer crystallographic distances (d_c) calculated from the putative γ-haemolysin pore [6] based on the α-toxin pore [19] and the monomer–monomer distances obtained by FRET (d_e) (see the Appendix). Both values are in Å. E is the degree of transfer calculated as described in the Appendix. Mean values are averaged over two to four different experiments; standard errors on E are 10–15%, which lead to 20–30% error on d_e.

FRET couple	E	dc	de
HlgAr+HlgBl	0.954	15	32
HlgAla+HlgBr	0.600	15	49
HlgAlb+HlgBr	0.432	10	55
HlgAla+HlgBl	0.360	39	58
HlgAr–HlgAlb+HlgB	0.079	38	80
HlgAr+HlgBr	0.060	34	84