AI-2 production in different species of Shewanella. Peak of AI-2 production during growth in different species of Shewanella and Alishewanella determined by the V. harveyi bioassay. AI-2 production is indicated as percent of positive controls (synthetic DPD or culture supernatant from V. harveyi BB152). Conditioned media of the strains were collected from two different cultures throughout growth (culture 1 and culture 2), and tested in the bioassay two times (1st assay and 2nd assay). The filling pattern indicates the type of cultivation medium used: dots, SM medium; vertical bars, LB medium; diagonal bars, MB medium; grid, LBSS medium; S. Shewanella; A. Alishewanella.