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A combined system of an anaerobic baffled reactor (ABR), a down-flow hanging sponge (DHS) reactor, an aquarium tank (AT), and a constructed wetland (CWL) was proposed as a new concept for sewage treatment. The ABR and DHS reactor, AT, and CWL were applied for biological sewage treatment, bioassay, and nutrient removal with food production, respectively. Killifishes and tomatoes were cultivated in the AT and CWL, respectively. In the ABR, 81.3% of total chemical oxygen demand and 76.5% of total biochemical oxygen demand were removed at 5.1 h of hydraulic retention time (HRT). Most remaining organic matter and 47.1% of ammonia were removed in the DHS reactor. In the CWL, 97.0% of total inorganic nitrogen and 78.6% of phosphate were removed with 3.87 kg/m2 of tomatoes producing yield at 4.4 days of HRT. In addition, anaerobic ammonium-oxidizing bacteria Candidatus Scalindua and ammonia-oxidizing bacteria Nitrospira and Nitorosococcus were considered as contributors to nitrogen removal in the CWL. The final effluent's water can be utilized as recycled water by installation of sand filtration and disinfection processes. Therefore, the proposed system can be applied as a low-energy, low-cost sewage treatment system with direct resource recovery. HIGHLIGHTS Anaerobic baffled reactor removed most of organic matters in sewage directly.; Foods for killifishes were automatically fed by sewage treatment.; Nutrients in sewage were consumed by tomatoes in constructed wetland.; Proposed system achieved direct resource recovery from sewage.

Strain CCI5, an oligotrophic bacterium, was isolated from leaf soil collected in Japan. Strain CCI5 grew at temperatures between 25 °C and 43 °C (optimum temperature, 40 °C) and at pHs between 6.0 and 10.0 (optimum pH, 9.0). Its major fatty acids were anteiso-C15:0 and iso-C16:0, and menaquinone 7 was the only detected quinone system. In a phylogenetic analysis based on 16S rRNA gene sequences, strain CCI5 presented as a member of the genus Paenibacillus. Moreover, multilocus sequence analysis based on partial sequences of the atpD, dnaA, gmk, and infB genes showed that strain CCI5 tightly clustered with P. glycanilyticus DS-1T. The draft genome of strain CCI5 consisted of 6,864,972 bp with a G+C content of 50.7% and comprised 6,189 predicted coding sequences. The genome average nucleotide identity value (97.8%) between strain CCI5 and P. glycanilyticus DS-1T was below the cut-off value for prokaryotic subspecies delineation. Based on its phenotypic, chemotaxonomic, and phylogenetic features, strain CCI5 (= HUT-8145T = KCTC 43270T) can be considered as a novel subspecies within the genus Paenibacillus with the proposed name Paenibacillus glycanilyticus subsp. hiroshimensis subsp. nov.

Strain AS-1 was isolated from laboratory-scale activated sludge collected in Japan. This strain not only grows on rich medium, including R2A medium, but also forms colonies on medium lacking organic matter other than agar (water agar), indicating it could be used as a eurytrophic recombinant host in material production processes. Here, we present a draft genome sequence of Enterobacter sp. AS-1, which consists of a total of 24 contigs containing 5,207,146 bp, with a GC content of 55.64%, and comprising 4,921 predicted coding sequences. Based on 16S rRNA gene sequence analysis, strain AS-1 was designated as Enterobacter sp. AS-1.

Strain CCI9, which was isolated from leaf soil collected in Japan, was capable of growth on poor-nutrient medium, at temperatures of 10°C to 45°C, at pHs of 4.5 to 10, and in the presence of 7.0% NaCl. We determined a draft genome sequence of strain CCI9, which consists of a total of 28 contigs containing 4,644,734 bp with a GC content of 56.1%. This assembly yielded 4,154 predicted coding sequences. Multilocus sequence analysis (MLSA) based on atpD, gyrB, infB, and rpoB gene sequences were performed to further identify strain CCI9. The MLSA revealed that strain CCI9 clustered tightly with Enterobacter roggenkampii EN-117T. Moreover, the average nucleotide identity value (98.6%) between genome sequences of strain CCI9 and E. roggenkampii EN-117T exceeds the cutoff value for prokaryotic subspecies delineation. Therefore, strain CCI9 was identified as E. roggenkampii CCI9. To clarify differences between E. roggenkampii EN-117T and CCI9, the coding proteins were compared against the eggNOG database.

An aerobic, oligotrophic, Gram-positive, non-sporulating, motile, rod-shaped, palladium-leaching bacterial strain, Deinococcus sp. KR-1, was previously isolated from pond water collected in Japan. This strain grew at 10 °C to 40 °C (optimum 30 °C), at pH 4.5 to 11.5 (optimum pH 8.0), and in the presence of 2.0% NaCl. Its major cellular fatty acids were C15: 1ω6 and C16 : 1ω7c. The quinone system was menaquinone 8. Multilocus sequence analysis based on partial sequences of four housekeeping genes (atpD, dnaA, gyrB and rpoB) showed that branching of Deinococcus sp. KR-1 was distant to those of Deinococcus type strains. The genome average nucleotide identity value between strain KR-1 and its closest related Deinococcus type strain was less than 95.69%. Based on its phenotypic, chemotaxonomic and phylogenetic data, strain KR-1 (= HUT-8138T = KCTC 33977T) can be considered a novel species within the genus Deinococcus with the proposed name Deinococcus kurensis sp. nov.

In this study, a two-stage down-flow hanging sponge (TSDHS) reactor was used as biotrickling filter for biogas desulfurization by utilizing the anaerobic digester supernatant (ADS) of sewage sludge of an activated sludge process (ASP). The reactor comprises a closed-type first-stage down-flow hanging sponge (1st DHS) and an open-type second-stage down-flow hanging sponge (2nd DHS) reactors. In the 1st DHS, hydrogen sulfide in biogas was dissolved into the ADS, and then it was oxidized into elemental sulfur and sulfate by microbe using dissolved oxygen and nitrite in the ADS. More than 99.9 % of hydrogen sulfide was removed within 400 s of empty bed residence time, and50 % of removed hydrogen sulfide was oxidized into elemental sulfur and accumulated at the surface of the sponge carrier in the 1st DHS. The 1st DHS effluent was fed into the 2nd DHS for nitrogen removal via nitrification and sulfur-based denitrification with the recirculation of the 2nd DHS effluent under nonaeration condition. In the 2nd DHS, 36.8 % of ammonia and 5.3 % of total inorganic nitrogen were removed. Sulfurimonas and Halothiobacillus were increased and contributed to the sulfur-based denitrification as well as the accumulation of elemental sulfur in the 1st DHS, respectively. In the 2nd DHS, Nitrosococcus, Nitrobacter, and Sulfuritalea were considered as the contributors of nitrogen removal via nitrification and sulfur-based denitrification. Further, this study shows that a TSDHS reactor can achieve not only desulfurization of biogas in the 1st DHS but also a 3.5 %-15 % reduction of the ammonia load in the 2nd DHS by effective utilization of the ADS during sewage treatment, assuming that the ADS is returned to the ASP.

Klebsiella pneumoniae subsp. pneumoniae CCI2 was isolated from leaf soil collected in Hiroshima Prefecture, Japan. The draft genome sequence comprises 78 contigs and contains 5,075,115 bp with a G+C content of 57.7%.

Klebsiella pneumoniae subsp. pneumoniae CCI2 was isolated from leaf soil collected in Hiroshima Prefecture, Japan. The draft genome sequence comprises 78 contigs and contains 5,075,115 bp with a G+C content of 57.7%.

Current pretreatment methods for wastewater from natural rubber (NR) factories either have low rubber recovery efficiency or are costly to operate. A wastewater treatment system was developed that combines a pretreatment canal (PTC) seeded with rubber, an anaerobic baffled reactor (ABR), and a down-flow hanging sponge (DHS) reactor. The PTC is simple to implement and contributes to not only rubber recovery but also organic matter removal in the ABR and nitrogen removal in the DHS reactor. In experiments, the PTC recovered 16.6% of residual rubber through coagulation. The ABR increased the chemical oxygen demand removal efficiency and methane recovery compared with other anaerobic reactors treating raw NR wastewater. The DHS reactor removed 30.7% of total inorganic nitrogen (TIN) by nitrification, anaerobic ammonia oxidation and denitrification. Feeding the bottom stage of the DHS reactor with sodium acetate solution increased the TIN removal efficiency to 87.8%. The water quality of the final effluent achieved the Vietnamese standards for the NR industry. Microbial community analysis was performed to identify the dominant microorganisms and mechanisms in the PTC, ABR, and DHS reactor.

Enterobacter oligotrophicus CCA3 was isolated from leaf soil collected in Hiroshima Prefecture, Japan. Here, we report the draft genome sequence of E. oligotrophicus CCA3. The draft genome sequence of E. oligotrophicus CCA3 consists of 29 contigs of 4,425,100 bp, with a GC content of 54.2%.

Strain CCI5, an oligotrophic bacterium, was isolated from leaf soil collected in Japan. Strain CCI5 grew at temperatures between 25 °C and 43 °C (optimum temperature, 40 °C) and at pHs between 6.0 and 10.0 (optimum pH, 9.0). Its major fatty acids were anteiso-C

Strain KR-1 was isolated from pond water collected in Japan. Because this strain was capable of adsorbing palladium particles in sterilized water, strain KR-1 will be a useful biocatalyst for palladium-leaching from metal waste. Here we present a draft genome sequence of Deinococcus sp. KR-1, which consists of a total of 7 contigs containing 4,556,772 bp with a GC content of 70.0% and comprises 4,450 predicted coding sequences. Based on the 16S rRNA gene sequence analysis, strain KR-1 was identified as Deinococcus sp. KR-1.

In this study, the microbial community for denitrification in the down-flow hanging sponge (DHS) reactor was estimated by batch experiment and microbial community analysis. Sludge retained from the DHS reactor, which conducts single-stage nitrification-denitrification, was collected into a series of vials as seed sludge for the batch experiment. Nitrate, nitrite, and nitrous oxide were added as nitrogen sources for each vial series. Sodium acetate solution was added to each vial series as a carbon source. At the beginning of the batch experiment, nitrous oxide was accumulated from only the nitrite-fed series (NO2 series). Approximately 50% of reduced nitrate was accumulated as nitrite in the nitrate-fed series (NO3 series). After two weeks of cultivation, nitrous oxide began to accumulate in the NO3 series without nitrite accumulation. Nitrous oxide accumulation was not confirmed in the NO3 series after 15 days of cultivation. During the batch experiment, the predominant denitrifying bacteria changed from Alicycliphilus to Thauera in the NO3 series. By contrast, the nitrous oxide producer Propionibacterium and the nitrous oxide reducer Staphylococcus increased in the NO2 series only. Thus, nitrite accumulation was considered to be a key factor for nitrous oxide emission in the DHS reactor. In addition, it was suggested that both nitrifying and denitrifying bacteria contributed to prevention of nitrite accumulation in the DHS reactor.