Leptospirillum spp. specific transcriptomic signatures in natural filamentous biofilm. A schematic cell showing the most relevant proteins whose genes are preferentially expressed in biofilm (red) or in planktonic cells (green). Yellow and orange symbols indicate that the genes are well expressed in both places but with no clear preferential pattern. The extended names of the genes and the hypothetical proteins or functions are indicated in Additional file 1 Table S2 (see also text for explanation). The main functional categories affected are indicated: Biofilm formation and maintenance, quorum sensing, specific proteases, chaperons, and cell wall components. EPS, exopolysaccharydes; LPS, lipopolysaccharydes.