FIG 7.

Working model showing how transcription factor SomA synchronously regulates biofilm formation and cell wall homeostasis. Transcription factor SomA plays a dual role in GAG and cell wall polysaccharides biosynthesis by direct binding to a conserved GTACTCCGTAC motif upstream of GAG biosynthetic genes (agd3 and ega3), GAG biosynthetic regulators (medA and stuA), and genes involved in cell wall polysaccharides chitin (chsE and chsF) and β-glucan (fks1) biosynthesis. Moreover, SomA globally regulates glucose uptake and utilization, as well as amino sugar and nucleotide sugar metabolism, which provides precursors for both GAG and cell wall polysaccharide biosynthesis.