The molecular with of e. coli dna is 2.5 x 10^9. The average molecular weight of a nucleotide pair is 660 and each pair contributes 0.34nm to the length of the DNA molecule. What’s the length of the dna molecule? If the average protein in e. coli consists of a chain of 400 amino acids, what’s the maximum number of proteins that can be coded by an e. coli dna molecule?