4 The Family Desulfobacteraceae

Desulfobacteraceae, a family within the order Desulfobacterales, embraces 21 genera Desulfobacter, Desulfatibacillum, Desulfatiferula, Desulfatirhabdium, Desulfatitalea, Desulfobacterium, Desulfobacula, Desulfobotulus, Desulfocella, Desulfococcus, Desulfoconvexum,Desulfofaba,Desulfofrigus,Desulfoluna,Desulfonatronobacter, Desulfonema, Desulforegula, Desulfosalsimonas, Desulfosarcina, Desulfospira, and Desulfotignum. The family is primarily defined by their 16S rRNA gene sequence phylogeny. Morphological and chemotaxonomic properties are highly variable for the delineation of genera and species. Strictly anaerobic, having a respiratory type of metabolism. Fermentative metabolism might occur. Members are either mesophilic or psychrophilic sulfate-reducing bacteria. Members of the family are mainly found in freshwater, brackish water, marine, and haloalkaline habitats. Most described species are chemoorganoheterotroph; some are chemolithoheterotroph or chemolithoautotroph. Most members oxidize organic substrates completely to carbon dioxide, whereas some perform an incomplete oxidation of organic substrates to acetate. This contribution is a modified and an updated version of a previous family description (Kuever et al. 2005a).