Lecturer: Mrs. Irit Levin Reisman
Affiliation: Racah Institute of Physics,
The Hebrew University of Jerusalem
Abstract:
Controlled experimental evolution during
antibiotic treatment can shed light on the
processes leading to antibiotic resistance
in bacteria. Recently, intermittent
antibiotic exposures have been shown to
lead rapidly to the evolution of tolerance,
i.e. the ability to survive under treatment
without developing resistance. However,
whether tolerance delays or promotes the
eventual emergence of resistance is
unclear. Here, we used in vitro evolution
experiments to explore this question. We
found that in all cases tolerance preceded
resistance. A mathematical population-
genetics model showed how tolerance
boosts the chances for resistance
mutations to spread in the population.
Thus, tolerance mutations pave the way
for the rapid subsequent evolution of
resistance. Preventing the evolution of
tolerance may offer a new strategy for
delaying the emergence of resistance.