Organization of archaeal flagellum (archaellum) genes in Nst1 and comparison to operons from Crenarchaeota ( S.a. ) and Euryarchaeota ( P.h. ). The archaella genes are in shaded rectangles. The numbers represent the gene loci in the genomes. Several paralogs of FlaI (Nst1_088, 227 and 260) and one FlaG paralog (Nst1_560) are not shown.