FIG. 7.

Model for the induction of genes involved in phaseolotoxin synthesis in P. syringae pv. phaseolicola growing at 18°C. The question mark represents an unknown signal-transducing element; TRR, specific motifs that have been postulated to be involved in the thermoregulation of phaseolotoxin synthesis; R₁, a repressor molecule that may bind to TRR motifs; I, inorganic moiety of phaseolotoxin (N′-sulfodiaminophosphinyl); R₂, an argK-specific repressor molecule. For an explanation of the model, see the text.