In the class we have discussed that bacteria can evolve much faster than animals
ID: 257759 • Letter: I
Question
In the class we have discussed that bacteria can evolve much faster than animals and plants because they grow much faster and have larger population sizes. To put this in a context, do you think it is possible statistically that every single base pair in the E. coli genome has experienced a mutation in a 5 ml E. coli overnight culture? We know that there are ~1010 cells in the 5 ml overnight culture and the mutation rate of E. coli is 10-9 per base pair per DNA replication. Justify you conclusion.
Explanation / Answer
Answer: Yes
Explanation:
Mutation rate = 10^-9 per bp per DNA replication
Incubation period = 12 hrs
Number of cells = 10^10
E coli genome size = 4.6 X 10^6 bp
E coli generation time = 20 min
Number of replication cycle in 12 hrs = (12 X 60)/20 = 36 cycles
Expected number of mutations in a single cell per one replication = 4.6 X 10^6 X 10^-9 = 4.6 X 10^-3 = 0.046
Expected number of mutations in 10^10 cells per one replication = 4.6 X 10^-3 X 10^10 = 4.6 X 10^7