Abstract
Here, we describe three endosymbiotic bacterial strains isolated from the gills of the shipworm, Bankia setacea (Teredinidae: Bivalvia). These strains, designated as Bs08(T), Bs12(T) and Bsc2(T), are Gram-stain-negative, microaerobic, gammaproteobacteria that grow on cellulose and a variety of substrates derived from lignocellulose. Phenotypic characterization, phylogeny based on 16S rRNA gene and whole genome sequence data, amino acid identity and percentage of conserved proteins analyses, show that these strains are novel and may be assigned to the genus Teredinibacter. The three strains may be differentiated and distinguished from other previously described Teredinibacter species based on a combination of four characteristics: colony colour (Bs12(T), purple; others beige to brown), marine salt requirement (Bs12(T), Bsc2(T) and Teredinibacter turnerae strains), the capacity for nitrogen fixation (Bs08(T) and T. turnerae strains) and the ability to respire nitrate (Bs08(T)). Based on these findings, we propose the names Teredinibacter haidensis sp. nov. (type strain Bs08(T)=ATCC TSD-121(T)=KCTC 62964(T)), Teredinibacter purpureus sp. nov. (type strain Bs12(T)=ATCC TSD-122(T)=KCTC 62965(T)) and Teredinibacter franksiae sp. nov. (type strain Bsc2(T)=ATCC TSD-123(T)=KCTC 62966(T)).