New research to be published January 13 in the journal Scientific Reports shows that some
bacterial1 cultures adopt an all-for-one/one-for-all strategy that would make a
socialist2 proud in preparing for the possibility of an
antibiotic3 onslaught. The findings could have application for how
persistent4 infections like those associated with cystic fibrosis are treated.
The paper, by three researchers at the University of Vermont, uses a series of time-lapse videos to show that single cells within a community of bacteria
randomly5 use a
cascade6 of proteins to become more or less antibiotic
resistant7, even when the community is not threatened by an antibiotic. A bacterial colony can
regenerate8 if only a few cells survive antibiotic treatment.
"It's
costly9 from a
metabolic10 standpoint for a cell to express the proteins that enable it to be resistant," said Mary Dunlop, assistant professor in the university's College of Engineering and Mathematics Sciences, and the paper's corresponding author. "This strategy allows a colony to hedge its bets by enabling individual cells within a population to assume high levels of resistance while others avoid this extra work."
Previous research has demonstrated that, when exposed to some
antibiotics11, all the cells within a bacterial population will use the protein cascade strategy,
activated12 by a
mechanism13 called MarA, to become resistant.
But the new study is among the first to show that colonies use the protein cascade strategy even when they are not under threat.
"This transient resistance, distributed in varying degrees among individual cells in a population, may be the norm for many bacterial populations," Dunlop said.