Figure 3. Supernatant cross-feeding experiments.
Total HAQ production in the WT and in the supernatant (S) of nonpolar mutants of genes from pqsABCDE operon involved in HAQ synthesis. In a second step (B) the supernatants of each mutant were added to cultures of all the other nonpolar mutants. As shown in Fig. S2, the active intermediate present in the culture supernatant of a nonpolar pqsB- or pqsC- mutant was ultimately identified as 2-ABA.