Table 1a:

Structures for which the helical axis is best described by a straight line.
Sigma2 of the straight line is significantly smaller (> 0.2) than for the next-best model(s). The structures are listed by the goodness of fit sigma2(straight line).

Number of structures: 177

PDB	NDB	IMB Jena Image Library	bp	molecule type	method	s(2)
1qaa	------	E   |    H   |    B	20	prot-nuc	model	0.000
1uqd	------	E   |    H   |    B	6	nuc	NMR	0.027
251d	bdf068	E   |    H   |    B	6	nuc	diff	0.048
1bce	------	E   |    H   |    B	6	nuc	NMR	0.049
1uqa	------	E   |    H   |    B	6	nuc	NMR	0.050
377d	arf0108	E   |    H   |    B	6	nuc	diff	0.055
1pbm	------	E   |    H   |    B	6	nuc	NMR	0.056
1n0o	------	E   |    H   |    B	6	nuc	NMR	0.062
1kfv	pd0277	E   |    H   |    B	6	prot-nuc	diff	0.067
282d	ddf069	E   |    H   |    B	6	nuc	diff	0.073
310d	arfs26	E   |    H   |    B	6	nuc	diff	0.081
224d	ddf052	E   |    H   |    B	6	nuc	diff	0.089
1buf	------	E   |    H   |    B	6	nuc	NMR	0.091
1uqb	------	E   |    H   |    B	6	nuc	NMR	0.091
1bcb	------	E   |    H   |    B	6	nuc	NMR	0.098
1lww	pd0322	E   |    H   |    B	7	prot-nuc	diff	0.103
1d21	ddfa14	E   |    H   |    B	6	nuc	diff	0.105
1d17	ddfa16	E   |    H   |    B	6	nuc	diff	0.107
1m5r	pd0334	E   |    H   |    B	6	prot-nuc	diff	0.108
1gj1	------	E   |    H   |    B	6	nuc	NMR	0.112
275d	adfb63	E   |    H   |    B	6	nuc	diff	0.116
1zqa	pde027	E   |    H   |    B	7	prot-nuc	diff	0.120
245d	ddf063	E   |    H   |    B	6	nuc	diff	0.120
1d1u	pd0152	E   |    H   |    B	6	prot-nuc	diff	0.125
1k9g	dd0047	E   |    H   |    B	6	nuc	diff	0.126
1ixy	pd0333	E   |    H   |    B	6	prot-nuc	diff	0.127
1l2b	pd0294	E   |    H   |    B	6	prot-nuc	diff	0.128
1f6c	bd0040	E   |    H   |    B	6	nuc	diff	0.136
1f69	bd0039	E   |    H   |    B	6	nuc	diff	0.142
1d22	ddfa15	E   |    H   |    B	6	nuc	diff	0.143
1lwv	pd0321	E   |    H   |    B	7	prot-nuc	diff	0.145
254d	adfb62	E   |    H   |    B	6	nuc	diff	0.145
1uqg	------	E   |    H   |    B	6	nuc	NMR	0.146
1i7j	ar0031	E   |    H   |    B	6	nuc	diff	0.147
1ih3	ad0022	E   |    H   |    B	6	nuc	diff	0.147
1p25	bd0064	E   |    H   |    B	6	nuc	diff	0.150
7icr	pde060	E   |    H   |    B	6	prot-nuc	diff	0.152
9ick	pde0100	E   |    H   |    B	6	prot-nuc	diff	0.153
7ick	pde053	E   |    H   |    B	6	prot-nuc	diff	0.154
1pbl	------	E   |    H   |    B	6	nuc	NMR	0.155
1uqf	------	E   |    H   |    B	6	nuc	NMR	0.162
1g00	ad0010	E   |    H   |    B	6	nuc	diff	0.163
182d	ddf049	E   |    H   |    B	6	nuc	diff	0.164
1p26	bd0065	E   |    H   |    B	6	nuc	diff	0.164
7ics	pde061	E   |    H   |    B	6	prot-nuc	diff	0.167
1l3z	ar0040	E   |    H   |    B	6	nuc	diff	0.169
256d	adfb72	E   |    H   |    B	6	nuc	diff	0.170
1m0e	pd0327	E   |    H   |    B	6	prot-nuc	diff	0.174
366d	ddf073	E   |    H   |    B	6	nuc	diff	0.176
1mtg	------	E   |    H   |    B	6	nuc	NMR	0.179
146d	------	E   |    H   |    B	6	nuc	NMR	0.180
7icn	pde056	E   |    H   |    B	6	prot-nuc	diff	0.181
9icl	pde0101	E   |    H   |    B	6	prot-nuc	diff	0.183
9icm	pde0102	E   |    H   |    B	6	prot-nuc	diff	0.183
1l1z	pd0293	E   |    H   |    B	6	prot-nuc	diff	0.185
7icg	pde049	E   |    H   |    B	6	prot-nuc	diff	0.187
1ih1	bd0050	E   |    H   |    B	6	nuc	diff	0.189
1s9b	bd0069	E   |    H   |    B	6	nuc	diff	0.194
9ico	pde0104	E   |    H   |    B	6	prot-nuc	diff	0.195
1dl8	dd0023	E   |    H   |    B	6	nuc	diff	0.196
9icp	pde0105	E   |    H   |    B	6	prot-nuc	diff	0.198
1n3a	pd0355	E   |    H   |    B	7	prot-nuc	diff	0.200
1i6j	pd0202	E   |    H   |    B	6	prot-nuc	diff	0.206
1k82	pd0264	E   |    H   |    B	6	prot-nuc	diff	0.209
7icp	pde058	E   |    H   |    B	6	prot-nuc	diff	0.211
9icu	pde0110	E   |    H   |    B	6	prot-nuc	diff	0.212
1n3c	pd0356	E   |    H   |    B	7	prot-nuc	diff	0.214
1uqe	------	E   |    H   |    B	6	nuc	NMR	0.216
9icn	pde0103	E   |    H   |    B	6	prot-nuc	diff	0.216
28dn	adh023	E   |    H   |    B	8	nuc	diff	0.218
7icm	pde055	E   |    H   |    B	6	prot-nuc	diff	0.221
9icq	pde0106	E   |    H   |    B	6	prot-nuc	diff	0.222
9icx	pde0113	E   |    H   |    B	6	prot-nuc	diff	0.222
452d	dd0012	E   |    H   |    B	6	nuc	diff	0.224
1lwy	pd0323	E   |    H   |    B	7	prot-nuc	diff	0.226
1g5k	------	E   |    H   |    B	6	nuc	NMR	0.231
1ih4	ad0023	E   |    H   |    B	6	nuc	diff	0.234
465d	dd0015	E   |    H   |    B	6	nuc	diff	0.234
367d	ddf074	E   |    H   |    B	6	nuc	diff	0.235
7ict	pde062	E   |    H   |    B	6	prot-nuc	diff	0.235
7icl	pde054	E   |    H   |    B	6	prot-nuc	diff	0.242
1qch	------	E   |    H   |    B	6	nuc	NMR	0.243
5ana	adh024	E   |    H   |    B	8	nuc	diff	0.245
1l1t	pd0292	E   |    H   |    B	6	prot-nuc	diff	0.247
1d37	ddf028	E   |    H   |    B	6	nuc	diff	0.248
7ice	pde047	E   |    H   |    B	6	prot-nuc	diff	0.251
1ih2	ad0021	E   |    H   |    B	6	nuc	diff	0.259
1d3r	bd0017	E   |    H   |    B	6	nuc	diff	0.263
7ico	pde057	E   |    H   |    B	6	prot-nuc	diff	0.263
1cx3	------	E   |    H   |    B	6	nuc	NMR	0.264
9icw	pde0112	E   |    H   |    B	6	prot-nuc	diff	0.265
7icq	pde059	E   |    H   |    B	6	prot-nuc	diff	0.269
1kci	dd0048	E   |    H   |    B	6	nuc	diff	0.271
1em0	dd0027	E   |    H   |    B	6	nuc	diff	0.276
1k2k	------	E   |    H   |    B	6	nuc	NMR	0.276
234d	ddf054	E   |    H   |    B	6	nuc	diff	0.277
9ict	pde0109	E   |    H   |    B	6	prot-nuc	diff	0.284
9icr	pde0107	E   |    H   |    B	6	prot-nuc	diff	0.285
1n39	pd0357	E   |    H   |    B	7	prot-nuc	diff	0.288
1lyr	------	E   |    H   |    B	7	prot-nuc	model	0.297
1k2j	------	E   |    H   |    B	6	nuc	NMR	0.303
206d	bdf062	E   |    H   |    B	6	nuc	diff	0.303
385d	ddf078	E   |    H   |    B	6	nuc	diff	0.305
1uqc	------	E   |    H   |    B	6	nuc	NMR	0.311
7ici	pde051	E   |    H   |    B	6	prot-nuc	diff	0.315
1q2r	pr0101	E   |    H   |    B	6	prot-nuc	diff	0.319
1d97	bdfp24	E   |    H   |    B	6	nuc	diff	0.320
235d	ddf055	E   |    H   |    B	6	nuc	diff	0.324
1zqd	pde030	E   |    H   |    B	7	prot-nuc	diff	0.325
1agl	ddf072	E   |    H   |    B	6	nuc	diff	0.327
198d	ddf050	E   |    H   |    B	6	nuc	diff	0.329
9ics	pde0108	E   |    H   |    B	6	prot-nuc	diff	0.342
1q2s	pr0102	E   |    H   |    B	6	prot-nuc	diff	0.343
288d	ddf065	E   |    H   |    B	6	nuc	diff	0.344
7icj	pde052	E   |    H   |    B	6	prot-nuc	diff	0.353
1d36	ddf026	E   |    H   |    B	6	nuc	diff	0.354
258d	ddf064	E   |    H   |    B	6	nuc	diff	0.355
1c9z	dd0018	E   |    H   |    B	6	nuc	diff	0.359
236d	ddf056	E   |    H   |    B	6	nuc	diff	0.361
7icv	pde088	E   |    H   |    B	6	prot-nuc	diff	0.361
1d67	ddf038	E   |    H   |    B	6	nuc	diff	0.366
1ih6	ad0024	E   |    H   |    B	6	nuc	diff	0.366
1x95	------	E   |    H   |    B	6	nuc	NMR	0.369
1imr	ddf061	E   |    H   |    B	6	nuc	diff	0.370
1p24	bd0063	E   |    H   |    B	6	nuc	diff	0.371
276d	ddf066	E   |    H   |    B	6	nuc	diff	0.372
386d	ddf079	E   |    H   |    B	6	nuc	diff	0.374
1msw	pd0345	E   |    H   |    B	6	prot-nuc	diff	0.379
2d34	ddfb24	E   |    H   |    B	6	nuc	diff	0.381
2bpf	pde011	E   |    H   |    B	7	prot-nuc	diff	0.384
7icf	pde048	E   |    H   |    B	6	prot-nuc	diff	0.385
152d	ddf045	E   |    H   |    B	6	nuc	diff	0.391
1ims	ddf062	E   |    H   |    B	6	nuc	diff	0.393
1d11	ddf001	E   |    H   |    B	6	nuc	diff	0.395
1d12	ddf019	E   |    H   |    B	6	nuc	diff	0.405
1d15	ddf022	E   |    H   |    B	6	nuc	diff	0.407
1d10	ddf020	E   |    H   |    B	6	nuc	diff	0.422
151d	ddf044	E   |    H   |    B	6	nuc	diff	0.430
7ich	pde050	E   |    H   |    B	6	prot-nuc	diff	0.433
1p20	dd0056	E   |    H   |    B	6	nuc	diff	0.434
1d38	ddf029	E   |    H   |    B	6	nuc	diff	0.442
257d	adf073	E   |    H   |    B	6	nuc	diff	0.445
482d	dd0017	E   |    H   |    B	6	nuc	diff	0.446
215d	ddf053	E   |    H   |    B	6	nuc	diff	0.453
1d33	ddf023	E   |    H   |    B	6	nuc	diff	0.455
1d35	ddfb25	E   |    H   |    B	6	nuc	diff	0.455
1d58	ddf036	E   |    H   |    B	6	nuc	diff	0.467
185d	------	E   |    H   |    B	6	nuc	NMR	0.470
7icu	pde063	E   |    H   |    B	6	prot-nuc	diff	0.472
332d	ahh089	E   |    H   |    B	6	nuc	diff	0.475
1d14	ddfp21	E   |    H   |    B	6	nuc	diff	0.486
1ao1	------	E   |    H   |    B	6	nuc	NMR	0.494
1p51	pd0426	E   |    H   |    B	6	prot-nuc	diff	0.503
203d	------	E   |    H   |    B	8	nuc	NMR	0.506
1oup	pd0403	E   |    H   |    B	8	prot-nuc	diff	0.514
380d	ddfb76	E   |    H   |    B	6	nuc	diff	0.531
2des	ddf041	E   |    H   |    B	6	nuc	diff	0.557
308d	ddfb70	E   |    H   |    B	6	nuc	diff	0.590
1cp8	------	E   |    H   |    B	8	nuc	NMR	0.631
1d54	ddf035	E   |    H   |    B	6	nuc	diff	0.634
1da0	ddf018	E   |    H   |    B	6	nuc	diff	0.639
278d	ddf068	E   |    H   |    B	6	nuc	diff	0.663
110d	ddf039	E   |    H   |    B	6	nuc	diff	0.676
418d	dr0001	E   |    H   |    B	6	nuc	diff	0.729
277d	ddf067	E   |    H   |    B	6	nuc	diff	0.776
343d	adfb97	E   |    H   |    B	6	nuc	diff	0.778
1vaq	dd0063	E   |    H   |    B	8	nuc	diff	0.821
2da8	------	E   |    H   |    B	6	nuc	NMR	0.855
1l2d	pd0296	E   |    H   |    B	6	prot-nuc	diff	0.859
1da9	ddf040	E   |    H   |    B	6	nuc	diff	0.865
1qda	dd0022	E   |    H   |    B	6	nuc	diff	0.886
1nab	dd0054	E   |    H   |    B	6	nuc	diff	0.887
1n0k	------	E   |    H   |    B	6	nuc	NMR	0.897
1eki	------	E   |    H   |    B	8	nuc	NMR	0.962
1i5v	------	E   |    H   |    B	6	nuc	NMR	1.326
1j7t	dr0006	E   |    H   |    B	6	nuc	diff	1.360
1l2c	pd0295	E   |    H   |    B	6	prot-nuc	diff	1.543

Abbreviations