Paul D. Sniegowski, Philip J. Gerrish, and Richard E. Lenski. Evolution of high mutation rates in experimental populations of E. coli. Nature, 387:703--705, 12 June 1997.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....operators are explicable in terms of selection pressures which are present in naturally evolving populations. For example, natural selection, ceteris paribus, favours genotypes which (i) have relatively low mutation rates, and (ii) are reasonably far from non viable mutants [10, 11] but see [12, 13]) Between them, these two selective forces can account for the biases exhibited by the most straightforward mutation operators considered here (Absorb, Repeat, and Replace) However, the biases of the operators designed specifically to negate these selection pressures (e.g. Ignore, Reflect and ....

Sniegowski, P.D., Gerrish, P.J., Lenski, R.E.: Evolution of high mutation rates in experimental populations of E. coli. Nature 387 (1997) 703--705

....3 shows the fitness of one of our hill climbers as a function of time, and we can clearly see the steps in this function where the climber finds its way onto a neutral network of higher fitness. Similar steps have been seen, for example, in laboratory experiments on the evolution of bacteria [21,22]. Although it appears in the figure that nothing happens in the periods between these jumps, it is at these times that the climber diffuses around its network, testing new mutations to find one of higher fitness. It is this diffusive motion which allows us to find higher fitness sequences on ....

P. D. Sniegowski, P. J. Gerrish, and R. E. Lenski, Evolution of high mutationrates in experimental populations of Escherichia Coli. Nature 387, 703 (1997).

....a way into another tissue of the host, where it causes harm. Again the virulent effects are maintained by the harmless trojan horses circulating in the population. Another possibility [7] is that the diversity created by within host competition overwhelms the immune system. It is also well known [8, 9] that mutation rates can be controlled by modifier genes. These can either be specific modifiers of particular loci, or modifiers which alter the mutation error checking mechanism thus changing the mutation rate of the entire genome. It has been suggested [10, 11] that these mechanisms can be ....

....in [12] One possible application of these ideas is to use mutation rates could be as a gauge to ascertain whether within host virulence evolution is present in a population. It may prove easier to measure the mutation rates of pathogens (see the Escherichia coli experiments described in [9]) than to measure their virulences directly. By combining the existing work on optimal rates of evolution in dynamic environments (e.g. 9, 10, 11] with theories of optimal mutation rates for within host virulence we may be able to give broad quantitative predictions for the correlation ....

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Paul D. Sniegowski, Philip J. Gerrish, and Richard E. Lenski. Evolution of high mutation rates in experimental populations of E. Coli. Nature, 387:703--705, 1997.

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Paul D. Sniegowski, Philip J. Gerrish, and Richard E. Lenski. Evolution of high mutation rates in experimental populations of E. coli. Nature, 387:703--705, 12 June 1997.

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Paul D. Sniegowski, Philip J. Gerrish, and Richard E. Lenski. Evolution of high mutation rates in experimental populations of E. coli. Nature, 387:703--705, 12 June 1997.

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