Random changes in behavior speed bacteria evolution
Computer modeling of how microbes mutate could provide clues to battling antibiotic resistance
PLAYING DEFENSE Random shifts in behavior could help disease-causing microbes like the bacterium Pseudomonas aeruginosa, pictured above, evolve antibiotic-resistance, a new study suggests.
James Archer/CDC
Random changes in microbes’ behavior can speed up evolution, a new study shows.
These shifts — called phenotype switches — can promote genetic mutations that help microbes better survive their environment, researchers report online January 19 at BioRxiv.org. Understanding how the microbes evolve is “particularly important for antibiotic resistance,” says study coauthor Bartlomiej Waclaw, a physicist at the University of Edinburgh.
Waclaw and colleagues used computer modeling to look at how an organism’s phenotype — in this case, its growth behavior — might influence its genetic makeup, or genotype, in an unchanging environment. The experiment could represent how bacteria replicate and evolve to reach an antibiotic-resistant state, the researchers suggest.
In the computer model, one growth behavior forced cells into a so-called “fitness valley,” a place where microbes don’t survive well. The other
