Fig. 1

Phylogenetic analysis of 77 putative response regulators. Most of the response regulators are classified by the relatedness of their output domains. Most response regulators in S. rimosus M4018 belong to OmpR and NarL families. Four response regulators in unclassified family did not fit to any known group (unclassified family). A group of response regulators designated as »Hybrid« represents the sensor kinase-response regulator family containing both transmitter and receiver modules in their primary amino acid sequences