. Author manuscript; available in PMC: 2011 Aug 11.

Published in final edited form as: J Am Chem Soc. 2010 Aug 11;132(31):10717–10727. doi: 10.1021/ja907225d

Table 2.

Comparison of helical parameters (averaged)

Entry	Structure	Type	Twist [°]	Rise [Å]	Base tilt [°]	Displacement [Å]	Bases per turn
1	This work, (AC)	γPNA-DNA	23.9	3.2	0.3	−5.5	15.1
	This work, (BD)	γPNA-DNA	23.3	2.9	2.3	−6.3	15.5
2	1NR8³⁹	αPNA-DNA	23.2	3.5	0.2	−3.8	15.5
3	1PDT⁴⁰	PNA-DNA	28.0	3.3	-	3.8	13
4	1PNN-triplex⁴¹	PNA₂-DNA	22.9	3.4	5.1	6.8	16
5	1HZS-(bT)-R⁴²	PNA-PNA	18	3.7	0.1	3.3	18
	1HZS-(bT)-L		−18	3.8	0.7	2.7	18
6	1XJ9-R⁴³	PNA-PNA	19.1	3.4	0.0	−3.5	19
	1XJ9-L		−18.0	3.3	0.0	7.9	20
7	1PUP-R⁴⁴	PNA-PNA	19.8	3.2	1.0	8.3	18
8	1RRU-R⁴⁵	PNA-PNA	20.5	3.2	0.0	7.7	18
	1RRU-L	PNA-PNA	19	3.4	0.0	6.6	18
9	1QPY-(N-Me)-R1⁴⁶	PNA-PNA	18.9	3.8	0.2	4.8	18
	1QPY-(N-Me)-R2	PNA-PNA	19	3.8	0.1	4.9	18
	1QPY-(N-Me)-L1	PNA-PNA	−20	3.5	0.0	7.2	18
	1QPY-(N-Me)-L2	PNA-PNA	−20	3.5	0.3	7.2	18
10	A-DNA⁴⁷		32.7	2.6	−4.5	−4.5	11
11	B-DNA⁴⁷		36.0	3.4	−0.1	0.0	10

	Sugar pucker	Intrastrand P distance [Å]	Dislocation of BP from helix axis [Å]	Rise [Å]	Tilt [°]
A-DNA	C3′-endo	5.9	4.0–4.9 major groove	2.56–3.29	10–20 Positive
B-DNA	C2′-endo	7.0	−0.02—1.8 minor groove	3.03–3.37	−5.9—16.4 negative

AC and BD refer to the two duplexes in the asymmetric crystallographic unit, with one duplex being the pairing of strands A and C, and the other of being strands B and D. P= interstrand phosphate-phosphate distance, BP = base-pair. Helical parameters were analyzed with CURVES.⁴⁸,⁴⁹