HOUSTON, March 22, 2011 In a study that literally analyzed competing bacteria fighting it out to the death, a University of Houston (UH) researcher and his colleagues identified evolutionary 'winners' and 'losers.' Continuing research to understand the basis of these fates may become a useful tool is designing roadblocks to antibiotic resistance.
In collaboration with scientists at Michigan State University (MSU), UH evolutionary biologist Timothy Cooper and his graduate student Utpala Shrestha were co-authors on a paper titled "Second-Order Selection for Evolvability in a Large Escherichia coli Population." The report appeared March 18 in Science, the world's leading journal of original scientific research, global news and commentary.
"The project found that bacteria growing for thousands of generations in an environment containing glucose as the only food had evolved to be better at getting better," Cooper said. "We found that two lineages of bacteria arose and competed in a single experimental population. The lineage that initially grew more slowly, yet had the potential to evolve more rapidly, was the evolutionary 'winner.' This is surprising because it's usually thought that competition is decided by what competitors can do now and not what they are capable of in the future."
As genetic changes occurred, making some individuals better competitors on the glucose food, other individuals that did not quickly get their own beneficial mutations were outcompeted and went extinct. Down the line, understanding the benefits of evolving quickly like this will be a useful tool to predict such things as antibiotic resistance and the evolution of infectious disease. Cooper said this knowledge may one day help scientists design intervention strategies that make the evolution of these traits less likely to occur.
The work done by Cooper and Shrestha at UH established the specific genetic changes occurring during this ba
|Contact: Lisa Merkl|
University of Houston