Table 1.

Image data and processing statistics

	Untreated tubes	Closed class		Open class
	(No ACh)	Ref(− ACh)	Spray	Ref(+ ACh)	Spray
Helical families	(− 16,6), (− 18,6)	(− 15,5)	(− 15,5), (− 17,5)	(− 15,5)	(− 15,5), (− 17,5)
No. of images	72, 24	28	55, 28	28	67, 28
Tube diameters (Å)	770, 830	710	710, 760	710	710, 760
Molecules averaged	2.4 × 105	5.9 × 104	1.8 × 105	6.7 × 104	2.0 × 105
Mean defocus (μm ± SD)	1.31 ± 0.24	1.46 ± 0.22	1.38 ± 0.24	1.43 ± 0.21	1.42 ± 0.21
Segment length (Å ± SD)a	602 ± 29	602 ± 29	597 ± 30	598 ± 31	591 ± 30
Resolution (Å)b	6.5	6.2		6.2

^aLength along tube used in distortion correction.

^bResolution estimated by FSC_0.5 criterion (Fig. S3).