Pseudomonadaceae

Pseudomonadaceae is family of bacteria which includes the genera Azomonas, Azomonotrichon, Azorhizophilus, Azotobacter, Cellvibrio, Mesophilobacter, Pseudomonas (the type genus), Rhizobacter, Rugamonas, and Serpens. The family Azotobacteriaceae was recently published as belonging in this family, as well.

History

Pseudomonad literally means false unit, being derived from the Greek pseudo (ψευδο - false) and monas (μονος - a single unit). The term "monad" was used in the early history of microbiology to denote single-celled organisms. Because of their widespread occurrence in nature, the pseudomonads were observed early in the history of microbiology. The generic name Pseudomonas created for these organisms was defined in rather vague terms in 1894 as a genus of Gram-negative, rod-shaped, and polar-flagella bacteria. Soon afterwards, a very large number of species was assigned to the genus. Pseudomonads were isolated from many natural niches, and several species names were originally assigned to the genus. New methodology and the inclusion of approaches based on the studies of conservative macromolecules have reclassified many strains.