Fig 3.

Multiple sequence alignment of three homologous MarR family members, PenR from the pen gene cluster of S. exfoliatus, PntR from the pnt gene cluster of S. arenae, and SAV_2989 from the ptl (neopentalenolactone) gene cluster of S. avermitilis. The multiple protein sequence alignment was generated using BioEdit and secondary structures predicted using Phyre2 (http://www.sbg.bio.ic.ac.uk/phyre2/html/page.cgi?id=index). α-Helices are represented as green boxes, and β-strands are represented as blue arrows. The region from residues 65 to 100 encompassing the α3 and α4 helices and the β1 and β2 strands corresponds to the established DNA-binding winged helix-turn-helix fold of MarR and related proteins.