Abstract
Fluviicola taffensis O'Sullivan et al. 2005 belongs to the monotypic genus Fluviicola within
the family Cryomorphaceae. The species is of interest because of its isolated phylogenetic location in the genome-sequenced fraction of the tree of life. Strain RW262
T
forms a monophyletic lineage with uncultivated bacteria represented in freshwater 16S rRNA gene libraries. A
similar phylogenetic differentiation occurs between freshwater and marine bacteria in the
family Flavobacteriaceae, a sister family to Cryomorphaceae. Most remarkable is the inability
of this freshwater bacterium to grow in the presence of Na
+
ions. All other genera in the family Cryomorphaceae are from marine habitats and have an absolute requirement for Na
+
ions
or natural sea water. F. taffensis is the first member of the family Cryomorphaceae with a
completely sequenced and publicly available genome. The 4,633,577 bp long genome with
its 4,082 protein-coding and 49 RNA genes is a part of the Genomic Encyclopedia of Bacteria
and Archaea project.