easily differentiated from the wild-type strain under
CLSM after following the PEB electroporation protocol,
as previously described, and the GFP fragment
was detected by PCR (data not shown). Plasmid
pHAPII was very stable in W19 strain, even after
120 generations in non-selective broth, and about 85%
of GFP-tagged strain W19 showed fluorescence under
the fluorescence microscope. The growth rate of
W19 transformants was similar to that of the wild-type
strain on LB-agar medium (Fig. 2a), indicating that
the presence of plasmids did not interfere with normal
metabolism. Furthermore, the GFP-tagged strain
W19 had the same antagonist activity as the wild-type
strain against FOC, as shown by the inhibition zone in
the plate assay (Fig. 2b).