Question

What diameter is achieved after the circularisation step in prokaryotic DNA packaging?

Options

• ~350 µm

• ~1100 µm

• ~30 µm

• ~2 µm

Answer 1

After circularisation, prokaryotic DNA is compacted to approximately 350 micrometres in diameter. This represents the first level of compaction from the relaxed circular form (~1100 µm), followed by looping (40–50 loop domains) that further reduces the diameter to ~30 µm before final supercoiling.