Blastococcus saxobsidens sp nov., and emended descriptions of the genus Blastococcus Ahrens and Moll 1970 and Blastococcus aggregatus Ahrens and Moll 1970

Ten Gram-positive, aerobic bacterial strains with coccoid cells occurring singly, in pairs, tetrads and small aggregates were isolated from the surface of marble and calcareous stones. The pepticloglycan contained meso-diaminopimelic acid as the diagnostic diamino acid. The major menaquinone was MK-9(H-4). The cellular fatty acid pattern consisted mainly of iso-branched chain components. According to their phylogenetic position, the organisms are members of the family Geodermatophilaceae, clustering close to Blastococcus aggregatus DSM 4725(T). Based on a combination of phenotypic, chemotaxonomic and genotypic characteristics, strain BC444(T) and seven relatives group apart from strains BC412 (= DSM 44517) and BC521 (= DSM 44518), which themselves form two individual lineages. DNA-DNA reassociation studies revealed that members of the three lineages were only remotely related to B. aggregatus DSM 4725(T); as the strain-rich cluster containing BC444(T) shared low DNA similarity values with strains BC412 and BC521, it will be described as a novel species of Blastococcus, for which the name Blastococcus saxobsidens sp. nov. is proposed. The type strain is BC444(T) (= DSM 44509(T) = NRRL 24246(T)).