Amphritea japonica sp. nov. and Amphritea balenae sp. nov., isolated from the sediment adjacent to sperm whale carcasses off Kagoshima, Japan

1 Extremobiosphere Research Center, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2-15 Natsushima-cho, Yokosuka 237-0061, Japan 2 Center for Advanced Marine Research, Ocean Research Institute, The University of Tokyo, 1-15-1 Minamidai, Nakano-ku, Tokyo 164-8639, Japan Correspondence Masayuki Miyazaki miyazakim{at}jamstec.go.jp Two novel species were isolated from the sediment adjacent to sperm whale carcasses off Kagoshima, Japan, at a depth of about 230 m. The isolated strains, JAMM 1866 T , JAMM 1548 and JAMM 1525 T , were Gram-negative, rod-shaped, non-spore-forming and motile by means of a single polar or bipolar flagellum. Phylogenetic analysis based on 16S rRNA gene sequences of strains JAMM 1866 T and JAMM 1548 indicated a relationship to the symbiotic bacterial clone R21 of Osedax japonicus (100 % sequence similarity) and all three isolates were closely related to Amphritea atlantica (97.7–97.8 % similarity) within the class Gammaproteobacteria . The novel isolates were able to produce isoprenoid quinone Q-8 as the major component. The predominant fatty acids were C 16 : 0 , C 16 : 1 and C 18 : 1 , with C 12 : 1 3-OH present in smaller amounts. The DNA G+C contents of the three isolated strains were about 47 mol%. Based on differences in taxonomic characteristics, the three isolated strains represent two novel species of the genus Amphritea for which the names Amphritea japonica sp. nov. (type strain JAMM 1866 T =JCM 14782 T =ATCC BAA-1530 T ; reference strain JAMM 1548) and Amphritea balenae sp. nov. (type strain JAMM 1525 T =JCM 14781 T =ATCC BAA-1529 T ) are proposed. Abbreviations: ML, maximum likelihood; NJ, neighbour-joining The GenBank/EMBL/DDBJ accession numbers for the 16S rRNA gene sequences of strains JAMM 1866 T , JAMM 1548 and JAMM 1525 T are AB330881 –AB330883, respectively. Transmission electron micrographs of negatively stained cells of the two novel species described in this study are available with the online version of this paper.