FIGURE 2.

C. elegans detects CAI-1 and CAI-1 variants. a, chemotaxis indices for the V. cholerae AI, CAI-1, the interspecies AI, AI-2, the V. harveyi AI, HAI-1, and the P. aeruginosa AI, PAI-1, all at 100 μm. b, chemotaxis indices at 10, 50, and 100 μm CAI-1. c, 1 μm CAI-1 was applied to one scoring region in an adapted two spot assay (32). The time period (seconds) the nematodes spent in each scoring region was scored from 10 min of video recorded at 1 frame/s. d, chemotaxis indices for enamino-CAI-1 (Ea-CAI-1) and phenyl-CAI-1 (P-CAI-1) are compared with CAI-1. Values are the mean ± S.D. of triplicate assays from three independent experiments. For b–d, unequal two-tailed t tests were performed comparing data to the leftmost bar of each graph. *, p < 0.05. e, structures of molecules.