Basepairs involving WatsonCrick(W) edge of Adenine and Sugar(S) edge of Cytosine 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:C W:S Cis

62
2

Residue Nos. 3052(9)-3030(9) PDB ID 1VQO

N3-O2 ... N6-N7

C6-O2' ... N1-C4

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:C w:s Trans

3

Optimized Model Structure

N3-O2 ... C2-C4

C6-C1' ... N6-N7

C6-O2' ... N1-C5

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