Dear Peter,
           Your Mob sound interesting! If you did not see the paper in last
year's (?) Plant Physiology by Zhongmin Dong et al (from Margaret McCully's
lab at Ottawa) on a bacterial endophyte in sugar cane, then you might find
some useful techniques there. They demonstrated that this was an endogenous
beast, but I can't quite recall how.
 
        As far as permeablizing roots go, we have worked on arabidopsis
roots and can get reasonably good results with PFA fixation followed by a
1h extraction in EGTA followed by a brief pectinase digestion. This can
give us good localization of intracellular structures in cortex and
epidermal tissues. But to go deeper, with use of harsher digestions, we
find the root tissues break up extensively.
 
        Hope this helps,
                        Tobias
 
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       ___     ____   ^         ____        _____    Tobias I. Baskin
      /   \   /      / \       /    \      /        University of Missouri
     /    |  /      /   \     /           /        Biological Sciences
    /___ /  /__    /_____\   /           /__      109 Tucker Hall
   /       /      /       \  (          /        Columbia, MO 65211 USA
  /       /      /         \  \        /        voice: 314-882-0173
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