Sphingomonas alaskensis sp nov., a dominant bacterium from a marine oligotrophic environment

Seven Gram-negative strains, isolated in 1990 from a 10(6)-fold dilution se ries of seawater from Resurrection Bay, a deep fjord of the Gulf of Alaska, were identified in a polyphasic taxonomic study. Analysis of 16S rDNA sequ ences and DNA-homology studies confirmed the phylogenetic position of all s trains in the genus Sphingomonas and further indicated that all of the stra ins constitute a single homogeneous genomic species, distinct from all vali dly described Sphingomonas species. The ability to differentiate the specie s, both phenotypically and chemotaxonomically. from its nearest neighbours justifies the proposal of a new species name. Sphingomonas alaskensis sp. n ov., for this taxon. Strain LMG 18877(T) (= RB2256(T) = DSM 13593(T)) was s elected as the type strain.