Repression of Tropolone Production and Induction of a Burkholderia plantarii Pseudo-Biofilm by Carot-4-en-9,10-diol, a Cell-to-Cell Signaling Disrupter Produced by Trichoderma virens
Figure 2
Active principle from T. virens PS1-7 for repression of tropolone production by B. plantarii.
Tropolone production was semi-quantified by the density of dark crystallines formed by chelation of B. plantarii-produced tropolone with iron supplemented to the medium at 0.1 mM. Repression of tropolone production was observed in the area around the paper disc charged with solvent (A), the area around the paper disc charged with fraction 2 equivalent to 3 ml culture fluid (35 µg disc−1) (B), and with fraction 3 equivalent to 3 ml culture fluid (55 µg disc−1) (C). Red arrow indicates the typical tropolone-iron crystallines. Major component in the fractions 2 and 3 were identical with carot-4-en-9,10-diol. Its chemical structure including the relative configuration was shown in this figure.