Two novel actinomycete isolates, designated strains NEAU-A4T and NEAU-A3, were isolated from rhizosphere soil of wheat (Triticumaestivum L.) and characterized using a polyphasic approach. Morphological and chemotaxonomic characteristics of the two strains coincided with those of the genus Streptomyces . The 16S rRNA gene sequence analysis showed that the two isolates exhibited 99.6 % 16S rRNA gene sequence similarity with each other and that they were most closely related to Streptomyces violaceorectus DSM 40279T (98.8, 99.0 %). Phylogenetic analysis based on 16S rRNA gene sequences indicated that the two strains clustered together and formed a separate subclade. Furthermore, a combination of DNA–DNA hybridization results and some physiological and biochemical properties demonstrated that the two strains could be distinguished from its closest relative. Therefore, it is proposed that strains NEAU-A4T and NEAU-A3 should be classified as representatives of a novel species of the genus Streptomyces , for which the name Streptomyces tritici sp. nov. is proposed. The type strain is NEAU-A4T (=CGMCC 4.7393T=DSM 104540T).
A Gram-stain-positive, non-motile, yellow and rod-shaped actinobacterium, designated strain Brt-AT, isolated from oil-contaminated soil, grew at 15–40 °C, at pH 5.5–10.0 and at 0–2 % (w/v) NaCl concentration. This strain was characterized by a polyphasic approach. The 16S rRNA gene sequence analysis showed that strain Brt-AT belonged to the genus Tessaracoccus and is closely related to Tessaracoccus rhinocerotis YIM 101269T, Tessaracoccus flavescens SST-39T, Tessaracoccus defluvii LNB-140T and Tessaracoccus flavus RP1T (99.03, 97.00, 96.88, and 96.46 % gene sequence similarity, respectively). The predominant respiratory quinone was MK-9(H4); the major polar lipids were phosphatidylglycerol and diphosphatidylglycerol; the predominant polyamines were spermine and spermidine; and the major fatty acids were anteiso-C15 : 0 and iso-C15 : 0. The cell-wall peptidoglycan contained ll-diaminopimelic acid; and glucose and ribose were detected as diagnostic sugars from whole-cell hydrolysates. The DNA G+C content was 68.1 mol%. The DNA–DNA relatedness between strain Brt-AT and its closely related species of the genus Tessaracoccus were between 55.0–44.0 %, which fall below the threshold value of 70 % for the strain to be considered as novel. The morphological, physiological, chemotaxonomic and phylogenetic analyses clearly distinguished this strain from its closest phylogenetic neighbours. Thus, strain Brt-AT represents a novel species of the genus Tessaracoccus , for which the name Tessaracoccus terricola sp. nov. is proposed. The type strain is Brt-AT (=KEMB 9005-690T=KACC 19391T=JCM 32157T).
In our previous study based on hsp60 PCR-restriction fragment length polymorphism and 16S rRNA gene sequencing, we stated that the bifidobacterial strains isolated from the individual faecal samples of five baby common marmosets constituted different phylogenetically isolated groups of the genus Bifidobacterium . In that study, we also proposed that these isolated groups potentially represented novel species of the genus Bifidobacterium . Out of them, Bifidobacterium aesculapii , Bifidobacterium myosotis , Bifidobacterium tissieri and Bifidobacterium hapali , have been described recently. Another strain, designated MRM 8.19T, has been classified as member of the genus Bifidobacterium on the basis of positive results for fructose-6-phosphate phosphoketolase activity and analysis of partial 16S rRNA, hsp60, clpC, dnaJ, dnaG and rpoB gene sequences. Analysis of 16S rRNA and hsp60 gene sequences revealed that strain MRM 8.19T was related to B. tissieri DSM 100201T (95.8 %) and to Bifidobacterium bifidum ATCC 29521T (93.7 %), respectively. The DNA G+C composition was 63.7 mol% and the peptidoglycan structure was l-Orn(Lys)–l-Ser. Based on the phylogenetic, genotypic and phenotypic data reported, strain MRM 8.19T represents a novel taxon within the genus Bifidobacterium for which the name Bifidobacterium catulorum sp. nov. (type strain MRM 8.19T=DSM 103154T=JCM 31794T) is proposed.
A novel thermophilic actinomycete, designated strain 3-12XT, was isolated from mushroom compost in Guangxi University, Nanning, China. The novel isolate contained meso-diaminopimelic acid as the diagnostic diamino acid and the whole-cell sugars were glucose and ribose. The predominant menaquinones were MK-9(H4) and MK-9(H6). The polar phospholipids were diphosphatidylglycerol, hydroxy-phosphatidylethanolamine, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside, ninhydrin-positive phosphoglycolipids and glycolipids. Major fatty acids were so-C16 : 0 and C17 : 0. The G+C content of the genomic DNA was 74.6 %. The 16S rRNA gene sequence analysis showed that the closest phylogenetic neighbour of strain 3-12XT was Thermomonospora chromogena ATCC 43196T (97.0 %), other closely related strains all belonged to the family Streptosporangiaceae and showed more than 6 % divergence. The chemotaxonomic characteristics of strain 3-12XT were significantly different from Thermomonospora chromogena ATCC 43196T and DNA–DNA hybridization showed low relatedness (48.6–55.6 %) between them, so they should be different species. Thermomonospora chromogena was removed from the genus Thermomonospora by Zhang et al. 1998 on the basis of phylogenetic, chemotaxonomic and phenotypic evidence, but its taxonomic position remains uncertain. Based on the phenotypic and phylogenetic data, strain 3-12XT represents a novel species in a new genus in the family Streptosporangiaceae . The name Thermostaphylospora griseoalba gen. nov., sp. nov. is proposed. The type strain of Thermostaphylospora grisealba is 3-12XT (=DSM 46781T=CGMCC 4.7160T). We also propose transferring Thermomonospora chromogena Zhang et al. 1998 to Thermostaphylospora chromogena comb. nov. (type strain ATCC 43196T=JCM 6244T).