Basepairs involving Hoogsteen(H) edge of Adenine and Sugar(S) edge of Adenine is shown. Highlighted examples are found from RNA crystal structures obtained from PDB.

Base pairs stabilized by N-H...N/O type hydrogen bonds only

Basepair

(type & Orientation)

*Frequency

Example

Hydrogen bonding atoms with their precursors

A:A H:S Cis

23

Residue Nos.10(C)-11(C) PDB ID 1I6U

N1-N6...N3-C5

C4-N7...O2'-C8

Base pairs stabilized by C-H...N/O interactions along with N-H...N/O hydrogen bonds

Basepair

(type & Orientation)

*Frequency

Example

Hydrogen bonding atoms with their precursors

A:A h:s Trans

51/
2

Residue Nos.207(A)-113(A) PDB ID 1GID

N1-N6...N3-C6

N9-N7...C2-C5

* 1st and 2nd numbers in Frequency column represent the numbers of occurences as base pairs and as base triplets, respectively.