Question

How many base pairs are contained in E. coli DNA?

Options

• About 6.6 billion base pairs

• About 4.6 million base pairs

• About 146 base pairs

• About 200 base pairs

Answer 1

E. coli DNA contains approximately 4.6 million base pairs organised in a circular, negatively charged molecule. This DNA must be compacted 400–700 times to fit within the bacterial cell, which is only 2–3 micrometres in length, far shorter than the DNA's 1.1–1.36 mm perimeter.