Dyadobacter subterraneus sp. nov., isolated from hydrocarbon-polluted groundwater from an oil refinery in Hungary

A Gram-stain-negative, aerobic, non-spore-forming, rod-shaped bacterial strain (UP-52^T) was isolated from hydrocarbon-polluted groundwater located near an oil refinery in Tiszaujvaros, Hungary. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate belongs to the genus Dyadobacter in the family Cytophagaceae. Its closely related species are Dyadobacter frigoris (98.00 %), Dyadobacter koreensis (97.64 %), Dyadobacter psychrophilus (97.57 %), Dyadobacter ginsengisoli (97.56 %) and Dyadobacter psychrotolerans (97.20 %). The predominant fatty acids are summed feature 3 (C_16 : 1  ω7c and/or C_16 : 1  ω7c/C_16 : 1 ω6c), C_15 : 0 iso, C_16 : 1  ω5c and C_17 : 0 iso 3OH. The predominant respiratory quinone detected in strain UP-52^T is quinone MK-7. The dominant polar lipids are glycolipid, phosphoaminolipid, phospholipid and aminolipid. The DNA G+C content is 40.0 mol%. Flexirubin-type pigment was present. Based on these phenotypic, chemotaxonomic and phylogenetic results, UP-52^T represents a novel species of the genus Dyadobacter, for which the name Dyadobacter subterraneus sp. nov. is proposed. The type strain is UP-52^T (=NCAIM B.02653^T=CCM 9030^T).

Taibaiella lutea sp. nov., Isolated from Ubiquitous Weedy Grass

An aerobic, Gram-stain-negative, non-motile and rod-shaped bacterial strain, designated as KVB11^T was isolated from the root of plant Setaria viridis near Dongguk University. Phylogenetic analysis indicated that strain KVB11^T belonged to the genus Taibaiella of the family Chitinophagaceae. Comparative 16S rRNA gene analysis indicated that the strain KVB11^T has closest similarities to Taibaiella smilacinae PTJT-5 ^T (96.6%) and Taibaiella yonginensis THG-SC4^T (96.4%). Strain KVB11^T grew optimally at 25-28°C, at pH 7.0 and tolerates NaCl upto 1% (w/v) NaCl. Flexirubin-type pigments were present. Phylogenetic and phylogenomic trees based on 16S rRNA gene sequences and genomic sequences demonstrated that strain KVB11^T formed a distinct branch with all seven type strains of genus Taibaiella. MK-7 was identified as the predominant isoprenoid quinone. The polar lipid were phosphatidylethanolamine, one unidentified aminophosphoglycolipid, one unidentified aminoglycolipid and two unidentified phosphoglycolipids. C_15:0 (28.3%), iso-C_15:1 G (28.5%) and iso-C_17:0 3-OH (10.5%) were the major fatty acids of the strain KVB11^T. The DNA G + C content of the genomic DNA of novel isolate was determined to be 38.9%. The above results clearly confirmed that strain KVB11^T represents a novel species of the genus Taibaiella, for which the name Taibaiella lutea sp. nov. is proposed. The type strain is KVB11^T (= KACC 19904 ^T = NBRC 113690 ^T).

Evolution of microbial community during dry storage and recovery of aerobic granular sludge

Aerobic granular sludge (AGS) was imbedded in agar and stored at 4 °C for 30 days, and then the stored granules were recovered in a sequencing batch reactor fed real wastewater within 11 days. Variations in microbial community compositions were investigated during dry storage and recovery of AGS, aiming to elucidate the mechanism of granular stability loss and recovery. The storage and recovery of AGS involved microbial community evolution. The dominant bacterial genera of the mature AGS were Zoogloea (relative abundance of 22.39%), Thauera (16.03%) and Clostridium_sensu_stricto (11.17%), and those of the stored granules were Acidovorax (26.79%), Macellibacteroides (12.83%) and Pseudoxanthomonas (5.69%), respectively. However, the dominant genera were Streptococcus (43.64%), Clostridium_sensu_stricto (12.3.6%) and Lactococcus (11.47%) in the recovered AGS. Methanogens were always the dominant archaeal species in mature AGS (93.01%), stored granules (99.99%) and the recovered AGS (94.84%). Facultative anaerobes and anaerobes proliferated and dominated in the stored granules, and their metabolic activities gradually led to granular structure destruction and property deterioration. However, the stored granules served as carriers for the microbes originated from the real septic tank wastewater during recovery. They proliferated rapidly and secreted a large number of extracellular polymeric substances which helped to recover the granular structure in 11 days.

Taibaiella helva sp. nov., isolated from farmland soil in China

A yellow-coloured bacterial strain, designated F-4T, was isolated from a farmland soil sample from Qianshan, Anhui province, China. Strain F-4T was Gram-stain-negative, strictly aerobic, oval-shaped, motile (by gliding) and non-spore-forming. Growth occurred at 20–35 °C (optimum, 30 °C), at pH 6.0–8.0 (pH 7.0) and with 0–1.0 % (w/v) NaCl (0 %). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain F-4T belonged to the genus Taibaiella . 16S rRNA gene sequence similarity values between strain F-4T and the type strains of the three recognized species of the genus Taibaiella , Taibaiella koreensis KACC 17171T, Taibaiella soli KCTC 42277T and Taibaiella chishuiensis JCM 19637T, were 98.1, 96.4 and 95.9 %, respectively. The predominant respiratory quinone was MK-7, with MK-8 as a minor component. The major polar lipids of strain F-4T were three unidentified lipids, two unidentified aminolipids, three unidentified phospholipids, an unidentified aminophospholipid and phosphatidylethanolamine. The major cellular fatty acids were iso-C15 : 0, iso-C15 : 1 G and iso-C17 : 0. The G+C content of the genomic DNA based on total genome calculations was 51.3 mol%. The major polyamine of strain F-4T was homospermidine. The average nucleotide identity and the digital DNA–DNA hybridization values for draft genomes between strain F-4T and strain THG-DT86T were 79.8 and 22.6 %, respectively. On the basis of the genotypic and phenotypic data presented here, strain F-4T represents a novel species of the genus Taibaiella , for which the name Taibaiella helva sp. nov. is proposed. The type strain is F-4T (=KCTC 62442T=CGMCC 1.13562T).

Edaphocola aurantiacus gen. nov., sp. nov., a new member of the family Chitinophagaceae isolated from wetland soil in South Korea

A short rod-shaped, yellow-orange pigmented, strictly aerobic bacterium, designated as strain H2^T, was isolated from the wetland soil of Halla Mountain, Jeju-island, South Korea. Growth was observed at temperatures of 10-30 °C (optimum at 25-30 °C), pH of 6-8 (optimum at pH 7), and salt concentrations of 0-1% (w/v) NaCl (optimum at 0%). The strain H2^T was found to be a catalase and oxidase-positive, non-motile, Gram-negative bacterium. On the basis of 16S rRNA gene sequence similarity and phylogenetic analysis, strain H2^T was found to be related to the members of the Chitinophagaceae family, being closely related to Taibaiella chishuiensis AY17^T (94.3% sequence similarity). The major polar lipids are phosphatidylethanolamine and glycolipid. Strain H2^T contained MK-7 as the only menaquinone as well as iso-C_15:0, iso-C_15:1 G and iso-C_17:0 3-OH as the major fatty acids (> 15%). The DNA G+C content of strain H2^T was determined to be 48.3 mol%. Based on the phylogenetic, phenotypic characteristics and chemotaxonomic analysis data, strain H2^T (= KCTC 62115^T = JCM 32353^T) should be classified as representative of a novel species of a novel genus within the family Chitinophagaceae, for which the name Edaphocola aurantiacus gen. nov., sp. nov., is proposed.

Variation of Bacterial and Archaeal Community Structures in a Full-Scale Constructed Wetlands for Wastewater Treatment

Microorganisms play important roles in the reduction of organic and inorganic pollutants in constructed wetlands used for the treatment of wastewater. However, the diversity and structure of microbial community in constructed wetland system remain poorly known. In this study, the Illumina MiSeq Sequencing of 16S rDNA was used to analyze the bacterial and archaeal microbial community structures of soil and water in a free surface flow constructed wetland, and the differences of bacterial communities and archaeal compositions between soil and water were compared. The results showed that the Proteobacteria were the dominant bacteria, making up 35.38%~48.66% relative abundance. Euryarchaeotic were the absolute dominant archaea in the influent sample with the relative abundance of 93.29%, while Thaumarchaeota showed dominance in the other three samples, making up 50.58%~75.70%. The relative abundances of different species showed great changes in bacteria and archaea, and the number of dominant species in bacteria was much higher than that in archaea. Compared to archaea, the community compositions of bacteria were more abundant and the changes were more significant. Meanwhile, bacteria and archaea had large differences in compositions between water and soil. The microbial richness in water was significantly higher than that in soil. Simultaneously, soil had a significant enrichment effect on some microbial flora.