NUCLEIC ACID STRUCTURE
C8C4
C2
C5
O2
C6
O4
N1
H6
N3
C5
C4
C2
H8
N9
N7
C4
C2’
N3
C1’
O4’
H5’’
O5’
P
O
H6
H1’
H5
O3’
H42
N1
H41
N3H3
N4
C6
O2
C5
C2
−O
O2’H2’
C3’
H5
C3’
H5’
H4’
H3’
H2’
C4’
C5’
H2’
C2’
H3’H4’
3
)7H(7C
H5’
O− H6
O4
O2
C2
C4C5
C6 N3H3
N1
O3’ H2’’
H1’
O
P
O5’
H5’’
O4’
C1’C4’
C5’
C6
H22
H21N3
C5
C4
C2
N2
O6
N1H1
H8
N9
N7
C8 N1
C6
H61
H62
N6
H2
G
U
C
A
T
0
N
N
N
N
N
N
N
N N
N
N
N
N
N
N
N
NN
N
N
0
0
00
0
0
00
0
0
90
18
36
54
72108
126
144
162
270
252
342
324
306
288
234
216
198
180
+
+
+
+
+
+
+
+
++
+
+
+
+ +
+
+
+
+
+
+ +
++
+
+
+
+
+
+
+
+
+
+
+
+
+
+
O4’−endo
C1’−endo
C3’−exo
+
C1’−exo
C4’−exo
+
+
C3’−endo
C2’−exo
+
O4’−exo
C4’−endo
C2’−endo
+
+
+
+
O
4
T TO
1
T
1
OT O
4T
1E
4
E
1
E 4E
4
3T
2
1
T
1
2
T
4
3
T
3
E
3E 2
E
2E
O
EOE
3
2
T
3
2
+
+
+
+
+
+
+
+
+
+
+
+
+
+
O
H O
H
H
H
N
HN
N
N
C
C
C C
N
N
O
O
N
C
C
C
C
C
O
H
HO
HH
Watson−Crick
Watson−Cricksacharid
Hoogsteen
sacharid
C−H
(=Hoogsteen)
O
O
C
C
C
C
C
N
N
N
N
N
N
CC
C
C
CH3
H
H
N
H
H
H
H
O
O
C
C
C
C
C
C
C
C
C
N
N
N
N
N
N
HH
H
H
H
N N
H
H
H
T = A C = G
N
N
N
N
N
C
C
C
H
O
H
C
H
C
N
C
H
C
H
N
C
N
C
H
C
H
C
H
N
H
N
N
N
O
N
C
N
C
N
C
C
C
C
N
C
N
C
H
C
H
O
H
O
H
C
C
O
O
H
H
H
H
N
O
O
H
C
CC H
C
C
H
H
H
N
H N
N
N
N
C
C
C
C
C
H
H
H
H
H
NN
H
H
H
H
H
N
N
N
N
N
N
C
C
C
C
C
C
C
C
C
A
G
A
C
A
U
DNA double helix B
DNA double helix A
z
xy
Stagger (Sz) Shear (Sx)
Shift (Dx)
y-displacement (dy) x-displacement (dx)
Stretch (Sy)
Rise (Dz) Slide (Dy)
z
x
y
Tip (θ) Inclination (η)
Buckle (κ)
Tilt (τ)
Propeller twist (ω)Opening (σ)
Twist (Ω) Roll (ρ)