Biochemistry DNA conformations

Helix rotation of A-DNA

Right handed

Base pairs per turn for A-DNA

roughly 11

Pitch per turn of helix in A-DNA

Roughly 25 angstroms

Proportions of A-DNA

Short and broad

Helix axis of A-DNA

Major groove

Sugar ring conformation of A-DNA

C3 endo

Glycosyl bond conformation of A-DNA

anti

Helix rotation of B-DNA

right-handed

Base pairs per turn of B-DNA

roughly 10

Pitch per turn of helix for B-DNA

roughly 33 angstroms

Proportions of B-DNA

Longer and thinner

Helix axis of B-DNA

through base pairs

Sugar ring conformations for B-DNA

C2 endo

Glycosyl bond conformation of B-DNA

anti

Helix rotation of Z-DNA

Left-handed

Base pairs per turn for Z-DNA

12

Pitch per turn for Z-DNA

roughly 46

Helix axis of Z-DNA

Minor groove

Sugar ring conformation of Z-DNA

Alternating

Glycosyl bond conformation of Z-DNA

anti at C, syn at G