The Base Pair Directory
| AC base pairs with two standard hydrogen bonds |
| base | potential H-bond donor/acceptor sites |
adenine A  |
A(da3) N6-H...C6 N1... |
A(da4) N6-H...C6 C5 N7... |
cytosine C  |
C(aa3) N3... C2 O2... |
C(da3) N4-H... C4 N3... |
| Base pairs with 4 heavy-atom H-bond donor/acceptor sites |
| base pair H-bond motif | structure images |
A(da3)...C(da3)
AC reverse wobble N1...H-N4 C6 C4 N6-H...N3 |
 |
A(da4)...C(da3)
AC reverse Hoogsteen N7...H-N4 C5 C4 C6 | N6-H...N3 |
| Base pairs with 3 heavy-atom H-bond donor/acceptor sites |
| base pair H-bond motif | structure images |
A(N6-H1/H2)...C(aa3)
AC N6-N3 N6-carbonyl H...N3 N6 C2 H...O2
|
 |
A(da4)...C(da3)
AC reverse Hoogsteen N7...H-N4 C5 C4 C6 | N6-H...N3
|
