Figure 2.

Structural model for PAS_Bvg. The modeled sequence encompasses residues 564–697 of BvgS, thus immediately following the predicted transmembrane segment of BvgS. The segment after the PAS core has not been modeled, because the corresponding segment is absent from the PAS_Hm X-ray structure. In BvgS this segment is predicted to form an α helix linking the PAS and kinase domains. In yellow are shown residues whose substitutions were previously reported to abolish the responsiveness of BvgS to negative modulation (see discussion).