To investigate the similarity of antagonistic ability between
the ion beam generated mutants and the wild type a dual culture
test was used in which more than 50 colonies were selected at
random from the bombarded bacterium. These bacteria initially
had the same inhibition ability compared to the control, but after
being exposed to the ion beam at an energy of 30 keV with a
fluence of 1016 ions/cm2
, one isolate of bacterium (MBL1) was
found to have lost antagonistic activity (Fig. 3). However, none
of the bacteria under vacuum without ion bombardment was
obtained (data not shown).
Moreover, the HAT–RAPD fingerprint using primer
OPAH10 presented an absence of DNA bands in comparison
between the mutant bacteria and wild type bacteria (Fig. 4).
Using four other primers (OPAH01, OPAH06, OPAH08 and
OPAH13), no difference in the band pattern was found between