Enlarged view of predicted Effector Binding Domain (EBD) of NodD1 dimer. S104 and K205 lie at the interface of regulatory domains I and II, the EBD, in this case, the flavonoid binding pocket. Both residues are in mutational hotspots where point mutations in other LysR-type transcriptional regulators display constitutively active or activation-deficient phenotypes thought to be a consequence of altered effector interactions.
Link to publication: http://jb.asm.org/content/195/16/3714.abstract
Melicent C. Peck, Robert F. Fisher, Robert Bliss and Sharon R. Long (2013) Isolation and Characterization of Mutant Sinorhizobium meliloti NodD1 Proteins with Altered Responses to Luteolin. Journal of Bacteriology 195:3714-3723.
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