Files in this Data Supplement:

• Supplemental file 1 - Table S1, prevalence of flagellar ORFs in Roseobacter clade genomes.
  PDF file, 106K.
• Supplemental file 2 - Fig. S1, conservation of the flagellin gene regulatory region.
  PDF file, 486K.
• Supplemental file 3 - Fig. S2, mutation in flaC does not affect chemotaxis.
  PDF file, 119K.
• Supplemental file 4 - Legends to Fig. S1 and S2.
  PDF file, 51K.