In article <4an7qj$lto at fs2.abdn.ac.uk>, gen113 at abdn.ac.uk (c.lagido) wrote:
> Hi,
> does anybody know how to isolate nonmotile mutants of Pseudomonas
fluorescens?
> Or to prevent motility of this bug somehow?
> Thanks,
> Cristina
> University of Aberdeen
> Scotland
Make an agar growth medium with a low "sloppy" concentration of agar
(about 0.35%). Pour plates. Inoculate the bacterium into the center of
the plate & incubate. As nutrients are depleted, bacteria will swim out
in a ring. Sample from the point of inoculation after a few days.
Nonmotile or nonchemotactic bacteria will be enriched here.
If necessary, repeat this selection for several cycles.
We used this approach to isolate motile variants of a bacterium (Lara
and Konopka, J. Gen. Micro. 133:1489-1494), but have subsequently found it
also works well for selection of nonmotile strains. Original idea comes
from Julius Adler's early work on bacterial chemotaxis.
Allan Konopka
