Sneathiella glossodoripedis sp nov., a marine alphaproteobacterium isolated from the nudibranch Glossodoris cincta, and proposal of Sneathiellales ord. nov and Sneathiellaceae fam. nov.

A novel marine bacterium, designated strain MKT133(T), was isolated from the foot epidermis of a nudibranch, Glossodoris cincta (Mollusca), collected in seawater off the coast of Japan at a depth of 4 m. This bacterium was Gram-negative, motile, mesophilic and strictly aerobic, with small rod-shaped cells. Colonies of the strain after 4-5 days incubation on marine agar 2216 at 30 degrees C were less than 1 mm in diameter. The strain required salt for growth and contained Q-10 as the predominant respiratory quinone, C-18:1 omega 7c, C-16:0 and C-17:1 as major cellular fatty acids and C-14:0 3-OH as a hydroxy fatty acid. 16S rRNA gene sequence analysis showed that the isolate had highest similarity to Sneathiella chinensis, with 97.2% sequence similarity to the type strain. Our phylogenetic analysis also revealed that this clade represents a distinct lineage and forms a deep branch with less than 90% 16S rRNA gene sequence similarity to the members of the eight known orders within the Alphaproteobacteria. Sufficient differences exist to distinguish this strain from Sneathiella chinensis. The name Sneathiella glossodoripedis sp. nov. is proposed, with the type strain MKT133(T) (=IAM 15419(T) =KCTC 12842(T)). The novel order Sneathiellales ord. nov. and family Sneathiellaceae fam. nov. are proposed for the distinct phyletic line represented by the genus Sneathiella.