Rubritalea spongiae sp. nov. and Rubritalea tangerina sp. nov., two carotenoid- and squalene-producing marine bacteria of the family Verrucomicrobiaceae within the phylum 'Verrucomicrobia', isolated from marine animals

1 Institute of Molecular and Cellular Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-Ku, Tokyo 113-0032, Japan 2 Marine Biotechnology Institute Co. Ltd, 3-75-1, Heita, Kamaishi, Iwate 026-0001, Japan Correspondence Jaewoo Yoon aa57058{at}mail.ecc.u-tokyo.ac.jp Two Gram-negative, non-motile, coccoid or rod-shaped, chemoheterotrophic bacteria designated strains YM21-132 T and YM27-005 T were isolated from marine animals, and were subjected to a polyphasic taxonomic examination. Phylogenetic analyses based on 16S rRNA gene sequences indicated that the two isolates belong to the genus Rubritalea of the phylum ‘ Verrucomicrobia ’ (subdivision 1). The novel isolates shared approximately 97–98 % sequence similarity with each other and showed 93–97 % similarity with Rubritalea species of the family Verrucomicrobiaceae . The level of DNA–DNA relatedness between strains YM21-132 T and YM27-005 T was less than 70 %, which is accepted as the phylogenetic definition of a species. Both strains produced reddish carotenoid pigments and squalene. The cell wall peptidoglycan of both strains contained muramic acid and meso -diaminopimelic acid. The G+C contents of the genomic DNA were 48.0 mol% (strain YM21-132 T ) and 50.3 mol% (strain YM27-005 T ). The presence of MK-8 and MK-9 as the major isoprenoid quinones, and iso-C 14 : 0 , iso-C 16 : 0 and C 16 : 1 7 c as the major cellular fatty acids supported the identification of the two novel strains as members of the genus Rubritalea . On the basis of polyphasic taxonomic studies, it was concluded that these strains should be classified as representing two novel, separate species in the genus Rubritalea within the phylum ‘ Verrucomicrobia ’, for which the names Rubritalea spongiae sp. nov. (type strain YM21-132 T =MBIC08281 T =KCTC 12906 T ) and Rubritalea tangerina sp. nov. (type strain YM27-005 T =MBIC08282 T =KCTC 12907 T ) are proposed. The GenBank/EMBL/DDBJ accession numbers for the 16S rRNA gene sequences of strains YM21-132 T and YM27-005 T are AB297805 and AB297806 , respectively.