Question

How do you calculate the number of bases in a DNA molecule? Please provide an example if you can. Thank you!

Answer 1

The distance between two consecutive base pairs is 0.34 X 10^-9m. The total number of base pairs of double helix DNA in an organism can be calculated by total length of double helix DNA / distance between two consecutive base pairs. Total number of base pairs = Total length of double helix DNA / distance between two consecutive bp. As for example: If length of E. Coli DNA is 1.36 mm, what is the number of base pairs in E. coli?
Let the total number of bp be x
1.36mm = x X 0.34 X 10^-9m
By solving this we get,
x = 4 X 10^6 bp
So the number of base pairs in E coli = 4 X 10^6 bp.