Basepairs involving WatsonCrick(W) edge of Adenine and Sugar(S) edge of Uracil 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:U W:S Cis

18

Residue Nos. 2823(A)-2047(A) PDB ID 2J01

C5-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:U w:s Trans

70/
1

Residue Nos. :21(W)-8(W) PDB ID 2J02

(1) N3-O2...C2-C5

C6-O2'...N6-N7

(2) N3-O2...C2-C5

C6-O2'...N1-C5

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