Question

Which bond in B-DNA will have to be rotated to convert it from syn to anti conformation?

• A. Hydrogen bond
• B. Glycosidic bond
• C. Phosphodiester
• D. Hydropbobic

Answer 1

The correct option is B Glycosidic bond

The C${}_1$ of pentose sugar in nucleotides is linked to the N1 or N9 position of pyrimidine or purine bases through a glycosidic bond. The syn and anti conformations, are the two conformational forms of nucleotides around this bond. The two forms are interconvertible by rotating the glycosidic bond without a need to break the bond.
So, the correct answer is option B.