Emendation of the description of Blastomonas natatoria (Sly 1985) Sly and Cahill 1997 as an aerobic photosynthetic bacterium and reclassification of Erythromonas ursincola Yurkov et al, 1997 as Blastomonas ursincola comb. nov.

Photosynthetic properties of Blastomonas natatoria (Sly 1985) Sly and Cahill 1997, which had been recognized as being non-photosynthetic, were examined and compared with those of its close relative, the aerobic photosynthetic bacterium, Erythromonas ursincola Yurkov et al. 1997. HPLC experiments demonstrated that bacteriochlorophyll a was present in a detectable amount in the lipid extract from B. natatoria DSM 3183(T) as well as that from E. ursincola DSM 9006(T). The puf genes, encoding the proteins of the photosynthetic reaction centre and core light-harvesting complexes, were detected by PCR from both the organisms. 16S rDNA sequence comparisons and DNA-DNA hybridization studies confirmed that B. natatoria and E. ursincola were closely related genetically in a single genus. On the basis of phenotypic, chemotaxonomic and phylogenetic data, it is proposed that the description of B. natatoria is emended as a species of aerobic photosynthetic bacteria and that E. ursincola is reclassified as Blastomonas ursincola comb. nov.