Speed increases as pair evolves together, study finds
Dr. Tony Brain/Science Source
WASHINGTON — Strand a fish on a tree stump, and neither swims away. But mixing two kinds of soil bacteria that are stationary on dry surfaces allows the combo — by means not yet clear— to expand unusually quickly, multiplying and oozing as a colony across a firm laboratory agar surface.
Over generations, the pair gets faster, Lucy McCully of the University of Massachusetts Dartmouth said August 6 at the 2nd American Society for Microbiology Conference on Experimental Microbial Evolution. She and coauthor Mark Silby are interested in what happens when bacterial species mingle and evolve together. Bacteria often get studied in colonies of single kinds, but real soil is a stew of many ingredients.
In McCully’s lab tests, neither Pseudomonas fluorescens Pf0-1 nor Pedobacter sp. V48 can move much at all without water. The Pseudomonas has a swimmer’s flagella but the researchers see no