An actinomycete, designated strain GIMV4.0001^T, was isolated from a forest soil sample in Vietnam. It produced white aerial mycelium and violet–blue diffusible pigment on Gause's synthetic agar. The substrate mycelium colour was not sensitive to pH. Micoscopic observations revealed that strain GIMV4.0001^T produced long, straight chains of cylindrical spores, and chemotaxonomic data confirmed that it belongs to the genus Streptomyces. Melanin was produced, but no antibacterial activity was evident against Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Candida albicans or Penicillium citrinum. Analysis of the 16S rRNA gene sequence of strain GIMV4.0001^T revealed that the highest similarity (99.4 %) was to Streptomyces bikiniensis ATCC 11062^T. However, the DNA–DNA relatedness between strain GIMV4.0001^T and S. bikiniensis ATCC 11062^T was found to be 50.3 %. Strain GIMV4.0001^T could also be differentiated from S. bikiniensis ATCC 11062^T and other Streptomyces species showing high 16S rRNA gene sequence similarity (98–99 %) based on morphological, physiological and biochemical characteristics. On the basis of its physiological and molecular properties, it is evident that strain GIMV4.0001^T represents a novel species of the genus Streptomyces, for which the name Streptomyces vietnamensis sp. nov. is proposed. The type strain is GIMV4.0001^T (=CCTCC M 205143^T=IAM 15340^T).

A Gram-stain-negative bacterial strain, designated 9NM-8^T, was isolated from an abandoned lead-zinc ore in Mei county, Meizhou, Guangdong province, PR China. The isolate was orange-pigmented, aerobic, oxidase- and catalase-positive, motile with lophotrichous flagella and rod-shaped. Strain 9NM-8^Tgrew optimally at pH 7.0 and 30 °C and in the absence of NaCl on R2A agar. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 9NM-8^Tbelongs to the genus Sphingomonas , with highest sequence similarities to Sphingomonas azotifigens KACC 14484^T(96.1 %), Sphingomonas trueperi DSM 7225^T(96.0 %) and Sphingomonas pituitosa DSM 13101^T(95.6 %). Strain 9NM-8^Tcontained Q-10 as the predominant ubiquinone. The major fatty acids included C_18 : 1ω7c, C_16 : 0, C_16 : 1ω7cand/or C_16 : 1ω6c(summed feature 3) and 11-methyl C_18 : 1ω7c. The DNA G+C content was 69.6±1.3 mol%. The major component in the polyamine pattern wassym-homospermidine and the polar lipid profile contained sphingoglycolipid, phosphatidylcholine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, an unidentified glycolipid and two unidentified phospholipids. Based on comparative analysis of physiological, chemotaxonomic and phylogenetic characteristics, strain 9NM-8^Tshould be considered to represent a novel species of the genus Sphingomonas , for which the nameSphingomonas guangdongensissp. nov. is proposed. The type strain is 9NM-8^T( = GIMCC 1.653^T = CGMCC 1.12672^T = DSM 27570^T).