Question

Non Watson-Crick base pairs are of biological importance. For example:

1. Hypoxanthine (6-oxopurine) is often one of the bases of the anticodon of tRNA. With what base on mRNA is hypoxanthine likely to pair? Draw the structure of this base pair.
2. The third position of the codon-anticodon interaction between tRNA and mRNA is often a G-U base pair. Draw a plausible structure for such a base pair
3. Mutations may arise during DNA replication when mispairing occurs as a result of the transient formation of a rare tautomeric form of a base. Draw a structure of a base pair with proper Watson-Crick geometry that contains a tautomeric form of adenine. What base sequence change would be caused in the replicated DNA by such a mispairing?

Answer 1