Streptomyces asenjonii sp. nov., isolated from hyper-arid Atacama Desert soils and emended description of Streptomyces viridosporus Pridham et al. 1958.

A polyphasic study was undertaken to establish the taxonomic status of Streptomyces strains isolated from hyper-arid Atacama Desert soils. Analysis of the 16S rRNA gene sequences of the isolates showed that they formed a well-defined lineage that was loosely associated with the type strains of several Streptomyces species. Multi-locus sequence analysis based on five housekeeping gene alleles showed that the strains form a homogeneous taxon that is closely related to the type strains of Streptomyces ghanaensis and Streptomyces viridosporus.

Rhodococcus jostii: a home for Rhodococcus strain RHA1.

The taxonomic position of Rhodococcus strain RHA1, an effective degrader of polychlorinated biphenyls with a large linear chromosome, was established using a polyphasic approach. The morphological and chemotaxonomic properties of the strain were typical of members of the genus Rhodococcus. The strain shared a high level of 16S rRNA sequence similarity (99.

Verrucosispora fiedleri sp. nov., an actinomycete isolated from a fjord sediment which synthesizes proximicins.

A novel filamentous actinobacterial organism, designated strain MG-37(T), was isolated from a Norwegian fjord sediment and examined using a polyphasic taxonomic approach. The organism was determined to have chemotaxonomic and morphological properties consistent with its classification in the genus Verrucosispora and formed a distinct phyletic line in the Verrucosispora 16S rRNA gene tree. It was most closely related to Verrucosispora maris DSM 45365(T) (99.

Verrucosispora wenchangensis sp. nov., isolated from mangrove soil.

An actinomycete strain 234402(T) was isolated from a mangrove soil sample collected in Wenchang, China. Phylogenetic analysis of the 16S rRNA gene sequence of strain 234402(T) indicated that the highest similarity was to Verrucosispora sediminis MS426(T) (99.25%).

Verrucosispora maris sp. nov., a novel deep-sea actinomycete isolated from a marine sediment which produces abyssomicins.

Verrucosispora isolate AB-18-032(T), the abyssomicin- and proximicin-producing actinomycete, has chemotaxonomic and morphological properties consistent with its classification in the genus Verrucosispora. The organism formed a distinct phyletic line in the Verrucosispora 16S rRNA gene tree sharing similarities of 99.7%, 98.

Reclassification of 'Dactylosporangium variesporum' as Saccharothrix variisporea corrig. (ex Tomita et al. 1977) sp. nov., nom. rev.

In the course of a polyphasic study it was observed that 'Dactylosporangium variesporum' NRRL B-16296 is misclassified in the genus Dactylosporangium as it exhibits properties consistent with its assignment to the genus Saccharothrix. Phylogenetic analyses based on 16S rRNA gene sequences show that the strain falls within the evolutionary radiation of the genus Saccharothrix, a result which is supported by corresponding chemotaxonomic and morphological markers. The strain is phylogenetically most closely, albeit loosely, related to Saccharothrix espanaensis, but can be readily distinguished from this and other species of the genus Saccharothrix with validly described names by using a range of phenotypic properties.

Albidopyrone, a new alpha-pyrone-containing metabolite from marine-derived Streptomyces sp. NTK 227.

Albidopyrone, a new alpha-pyrone-containing secondary metabolite, was produced by Streptomyces sp. NTK 227, a strain isolated from Atlantic Ocean sediment and found to be a member of the Streptomyces albidoflavus 16S rRNA gene clade. The structure of the compound was determined by MS and NMR spectroscopy, and found to have a moderate inhibitory activity against protein-tyrosin phosphatase B.

Diversity of culturable actinomycetes in hyper-arid soils of the Atacama Desert, Chile.

The Atacama Desert presents one of the most extreme environments on Earth and we report here the first extensive isolations of actinomycetes from soils at various locations within the Desert. The use of selective isolation procedures enabled actinomycetes to be recovered from arid, hyper-arid and even extreme hyper-arid environments in significant numbers and diversity. In some cases actinomycetes were the only culturable bacteria to be isolated under the conditions of this study.

Amycolatopsis regifaucium sp. nov., a novel actinomycete that produces kigamicins.

The taxonomic position of seven soil actinomycetes provisionally assigned to the genus Amycolatopsis was established in a polyphasic study. The isolates, which had identical 16S rRNA gene sequences, had closest similarity to the type strain of Amycolatopsis orientalis. A representative isolate, strain GY080T, had chemotaxonomic properties that were typical of the genus Amycolatopsis and could be distinguished from the type strain of A.