Hi All,

I'm interested in predator-prey dynamics, and would like to use D. discoideum-E. coli as a simple lab system.  For observations, I'm using a stereoscope at 50X with a combination of direct lighting and light reflected upward through the petri dish.  The growth medium is a thin layer of SM agar.  I'm not having any problems observing the amoebas on the agar surface, but they sure are hard to see on the bacterial colonies.  I can see little bumps crawling around the colony surface but they are pretty indistinct.  Any ideas on visualizing amoebas on bacterial colonies?  Would a GFP strain help?  Thanks for any help.

Cheers,
John D. Reeve


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John D. Reeve
Associate Professor
Department of Zoology
1125 Lincoln Drive
Southern Illinois University
Carbondale, IL 62901-6501
(618) 453-6670 (office)
(618) 453-2806 (fax) 
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http://www.zoology.siu.edu/people/reeve.html
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