Figure 1

Mangotoxin production by random miniTn 5 insertional mutants. Three pairs of mutants in different genes of the mbo and mgo operon, and in the gacS/gacA two-component regulatory system, obtained in previous works and tested for mangotoxin production. The corresponding disrupted gene is detailed in brackets. The P. syringae pv. syringae strains UMAF0158 (mangoxin-producing wilt-type strain) and B728a (nonproducing) were used as references. Mangotoxin production was evaluated using PMS minimal medium supplemented or not with ornithine. The results are indicated as follows: - absence of inhibition halo, + presence of inhibition halo, -* slight toxicity which was not reverted by addition of ornithine. Toxic activity reverted in presence of ornithine denotes the production of mangotoxin.