The DNA-binding assays of purified His-PhbF from H. seropedicae SmR1 to the promoter regions of phaP1, phbF, dskAphbC, fadBphbA, phbCphbB and H_sero3316phaB were performed as described in Material and Methods. DNA promoter regions used in the assays are indicated by vertical black arrow heads and numbers indicate base position related to the translation start of each gene. Panel A: DNA labeled with [32P]. Lanes 1 to 5 indicate increasing amounts of purified His-PhbF (0, 280, 570, 860 or 1100 nM). Panel B: Fluorescent labeled DNA. Lanes 1 to 8 indicate increasing amounts of purified His-PhbF (0, 62, 125, 250, 500, 750, 1000 or 1250 nM). Protein concentrations were calculated assuming His-PhbF as a tetrameric protein.