Chemotaxonomic Investigation of Heterotrophic, Aerobic and Microaerophilic Spirilla, the Genera Aquaspirillum, Magnetospirillum and Oceanospirillum

The cellular fatty acid compositions, isoprenoid quinones and G+C content of the DNAs of 34 strains of the genera Aquaspirillum, Magnetospirillum and Oceanospirillum were determined. On the basis of these chemotaxonomic characteristics, species of the genera of freshwater spirilla, Aquaspirillum and Magnetospirillum, were roughly divided into four groups: Aquaspirillum serpens (type species of the genus Aquaspirillum) and A. putridiconchylium; A peregrinum; Magnetospirillum gryphiswaldense (type species of the genus Magnetospirillum), M. magnetotacticum, A. polymorphum and A. itersonii; and a heterogeneous group including 10 species of the genus Aquaspirillum. Species of the genus Oceanospirillum, marine spirilla, were divided into three groups: Oceanospirillum linum (type species of the genus Oceanospirillum), O. maris, O. beijerinckii, O. multiglobuliferum, O. japonicum and O. minutulum; O. kriegii and O. jannaschii; and O. pusillum. Our classification based on the chemotaxonomic characteristics correlates well with that based on the results of DNA-rRNA hybridization; and it indicates that the genera Aquaspirillum and Oceanospirillum are taxonomically heterogeneous, while the genus Aquaspirillum should be restricted to the A. serpens group and the genus Oceanospirillum to the O. linum group.