Planomonospora algeriensis sp. nov., an actinobacterium isolated from a Saharan soil of Algeria.

A filamentous actinobacterium, designated strain PM3T, was isolated from a Saharan soil sample collected from Béni-Abbès, Béchar (South-West Algeria). A polyphasic taxonomic study was carried out to establish the status of strain PM3T. The isolate was found to have morphological and chemotaxonomical properties associated with members of the genus Planomonospora. The new isolated microorganism developed cylindrical sporangia arranged in double parallel rows on aerial mycelium, each one containing a motile single sporangiospore. The cell wall of the strain was found to contain meso-diaminopimelic acid. Whole-cell hydrolysates were found to contain madurose, glucose, mannose and ribose. The predominant menaquinone was identified as MK-9(H2) (69.6%). The polar lipids detected were identified as diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphatidylethanolamine, phosphatidylhydroxyethanolamine and glucosamine-containing lipids. The major fatty acids were found to be C17:1ω9c (38.6%) and C17:0 (24.2%). Results of 16S rRNA gene sequence comparison revealed that strain PM3T shared a high degree of 16S rRNA gene sequence similarity with Planomonospora sphaerica DSM 44632T (99.3%), Planomonospora parontospora subsp. parontospora DSM 43177T (99.2%) and P. parontospora subsp. antibiotica DSM 43869T (99.0%). DNA-DNA hybridization values between strain PM3T and the type strains of the closely related species were between 58.4 and 70.1%. The combination of phylogenetic analysis, DNA-DNA relatedness data, phenotypic characteristics and chemotaxonomic data support the conclusion that strain PM3T represents a novel species of the genus Planomonospora, for which the name Planomonospora algeriensis sp. nov. is proposed. The type strain is PM3T (=DSM 46752T = CECT 9047T).

Saccharothrix ghardaiensis sp. nov., an actinobacterium isolated from Saharan soil.

The taxonomic position of a new Saccharothrix strain, designated MB46T, isolated from a Saharan soil sample collected in Mzab region (Ghardaïa province, South Algeria) was established following a polyphasic approach. The novel microorganism has morphological and chemical characteristics typical of the members of the genus Saccharothrix and formed a phyletic line at the periphery of the Saccharothrix espanaensis subcluster in the 16S rRNA gene dendrograms. Results of the 16S rRNA gene sequence comparisons revealed that strain MB46T shares high degrees of similarity with S. espanaensis DSM 44229T (99.2%), Saccharothrix variisporea DSM 43911T (98.7%) and Saccharothrix texasensis NRRL B-16134T (98.6%). However, the new strain exhibited only 12.5-17.5% DNA relatedness to the neighbouring Saccharothrix spp. On the basis of phenotypic characteristics, 16S rRNA gene sequence comparisons and DNA-DNA hybridizations, strain MB46T is concluded to represent a novel species of the genus Saccharothrix, for which the name Saccharothrix ghardaiensis sp. nov. (type strain MB46T = DSM 46886T = CECT 9046T) is proposed.

Saccharothrix isguenensis sp. nov., an actinobacterium isolated from desert soil.

A novel actinobacterial strain, designated MB27T, was isolated from a Saharan soil sample collected in Mzab region (Ghardaïa province, South Algeria). Strain MB27T was characterized following a polyphasic taxonomic approach. This strain produced a branched and fragmented substrate mycelium, which was found to have a yellowish orange colour. A white scanty aerial mycelium was produced on most media tested. Chemotaxonomic and phylogenetic studies clearly demonstrated that strain MB27T belongs to the family Pseudonocardiaceae and is closely related to the genus Saccharothrix. Cell-wall hydrolysates contained meso-diaminopimelic acid but not glycine, and whole-cell hydrolysates contained galactose, glucose, ribose and small amounts of mannose and rhamnose. The detected phospholipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannosides. Mycolic acids were not detected while the predominant fatty acid was iso-branched hexadecanoate (iso-C16 : 0). The major menaquinone was MK-9(H4). Results of 16S rRNA gene sequence comparisons revealed that strain MB27T shairs the highest degree of similarity with Saccharothrix ecbatanensis DSM 45486T (99.8%), Saccharothrix hoggarensis DSM 45457T (99.3 %), Saccharothrix longispora DSM 43749T (98.6 %) and Saccharothrix yanglingensis DSM 45665T (98.6 %). However, it exhibited only 11-42 % DNA-DNA relatedness to the neighbouring Saccharothrixspecies. On the basis of phenotypic characteristics, 16S rRNA gene sequence comparisons and DNA-DNA hybridization, strain MB27T is shown to represent a novel species of the genus Saccharothrix, for which the name Saccharothrix isguenensis sp. nov. (type strain MB27T=DSM 46885T=CECT 9045T) is proposed.

Streptosporangium becharense sp. nov., an actinobacterium isolated from desert soil.

The taxonomic position of a novel actinobacterium, strain SG1T, isolated from a Saharan soil sample collected from Béni-Abbès, Béchar (south-west Algeria), was established by using a polyphasic approach. The micro-organism had morphological and chemical features that were consistent with its classification in the genus Streptosporangium. The cell-wall peptidoglycan contained meso-diaminopimelic acid. The whole-cell sugars contained ribose and glucose, but not madurose. The predominant menaquinones were MK-9(H2) and MK-9(H4). The polar lipid profile contained diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylhydroxymethylethanolamine, phosphatidylhydroxyethanolamine, phosphatidylglycerol, phosphatidylinositol and phosphatidylinositol mannosides. The predominant cellular fatty acids were C17 : 1ω8c, iso-C16 : 0, 10-methyl C17 : 0, C18 : 1ω9c and C17 : 0. 16S rRNA gene sequence similarity analysis supported the classification of the isolate in the genus Streptosporangium and indicated that it was related most closely to 'Streptosporangium subfuscum' DSM 46724 (99.7 % similarity), Streptosporangium pseudovulgare DSM 43181T (98.7 %), Streptosporangium fragile DSM 43847T (98.6 %) and Streptosporangium sandarakinum DSM 45763T (98.5 %). Phylogenetic analyses based on 16S rRNA gene sequences showed that strain SG1T formed a cluster with its closest relative 'S. subfuscum' DSM 46724. However, DNA-DNA relatedness as well as physiological and chemotaxonomical analyses showed that strain SG1T could be differentiated from its closest phylogenetic relatives. Therefore, it is proposed that strain SG1T should be classified as representing a novel species in the genus Streptosporangium, for which the name Streptosporangiumbecharense sp. nov. is proposed. The type strain is SG1T (=DSM 46887T=CECT 8961T).

Streptosporangium saharense sp. nov., an actinobacterium isolated from Saharan soil.

A novel actinobacterium, designated strain SG20T, was isolated from a Saharan soil sample collected from Béni-isguen (Mzab), Ghardaïa province, southern Algeria. The micro-organism developed small roundish sporangia on aerial mycelium that were sessile or carried by very short sporangiophores. The cell-wall peptidoglycan contained meso-diaminopimelic acid and the whole-cell sugars comprised glucose, ribose and mannose, but madurose was not detected. The predominant menaquinones were MK-9(H4), MK-9(H6) and MK-9(H2). The major fatty acids were iso-C16 : 0 and C16 : 0. The phospholipids detected were diphosphatidylglycerol, phosphatidylinositol, phosphatidylethanolamine and unknown lipids. The phenotypic and chemotaxonomic characteristics of the novel strain resembled those of recognized members of the genus Streptosporangium. Moreover, phylogenetic analysis based on a 16S rRNA gene sequence generated from the strain identified its closest relative as Streptosporangium jomthongense BCC 53154T (98.5 % similarity), which produces single spores on aerial mycelium, but no sporangia. In hybridization experiments, the DNA-DNA relatedness values recorded between strain SG20T and S. jomthongense DSM 46822T fell well below 70 %. On the basis of phenotypic and genotypic data, strain SG20T can be distinguished as representing a novel species of the genus Streptosporangium, for which the name Streptosporangium saharense sp. nov. is proposed. The type strain is SG20T ( = DSM 46743T = CECT 8840T).