Observational study for impact assessment of global warming on soil carbon dynamics at the 80N Canadian arctic circle region

課題番号：2040500

Microbial diversity in disturbed and undisturbed peat swamp forest and isolation of cyanobacteria

Microbial diversity from disturbed and undisturbed peat swamp forest obtained from next generation sequencing. Through this analysis, genera cyanobacteria is being compared with isolated cyanobacteria from both environmments which is extremely acidic. For the future study, this genera has ability as biofertilizer in acidic soil for plantations

Whole-Genome Sequence of the Microcystin-Degrading Bacterium Sphingopyxis sp. Strain C-1

This report describes the whole-genome sequence of an alkalitolerant microcystin-degrading bacterium, Sphingopyxis sp. strain C-1, isolated from a lake in China

Characteristics of a Microcystin-Degrading Bacterium under Alkaline Environmental Conditions

The pH of the water associated with toxic blooms of cyanobacteria is typically in the alkaline range; however, previously only microcystin-degrading bacteria growing in neutral pH conditions have been isolated. Therefore, we sought to isolate and characterize an alkali-tolerant microcystin-degrading bacterium from a water bloom using microcystin-LR. Analysis of the 16S rRNA gene sequence revealed that the isolated bacterium belonged to the genus Sphingopyxis, and the strain was named C-1. Sphingopyxis sp. C-1 can grow; at pH 11.0; however, the optimum pH for growth was pH 7.0. The microcystin degradation activity of the bacterium was the greatest between pH 6.52 and pH 8.45 but was also detected at pH 10.0. The mlrA homolog encoding the microcystin-degrading enzyme in the C-1 strain was conserved. We concluded that alkali-tolerant microcystin-degrading bacterium played a key role in triggering the rapid degradation of microcystin, leading to the disappearance of toxic water blooms in aquatic environments

Characterization of musty odor producing actinomycetes in Malaysia

The presence of geosmin and 2-methylisoborneol (2-MIB) becomes an increasing concern as they are known to cause earthy or musty odor in freshwater environments. Geosmin and 2-MIB outbreaks in Malaysia are not well understood and since Malaysia has a stable temperature throughout the year, no information has been reported on effect of temperature to the odor production. In this study, 6 isolated strains were selected for study of the effect of temperature (20, 25, 30, 35, 40, 45 & 50°C) on geosmin and 2-MIB production. Preliminary results indicate that at temperature 30 °C, Strain 5 showed highest geosmin production (129.06 µg/L) and Strain 2 produced highest 2-MIB (19.89 µg/L). PCR band was obtained in a test whether these isolated strains had geoA gene or not

Microcystin degradation in sphingopyxis sp. C-1

The microcystin-degrading gene cluster, mlrA-B-C-D, plaies an important role in the degradation process of hepatotoxic microcystins for several bacterial species. However after microcystin is degraded to linear-microcystin by MlrA, it is still unknown about where and by what it is metabolited. In order to clarify it, we disrupted the mlrB gene and mlrC gene in chromosome of microcystin-degrading bacteria, Sphingopyxis sp. C-1. The cells disrupted mlrB gene and mlrC gene accumulated of microcystin-degradation product, linear-microcystin and tetrapeptide, respectively, whereas the cell free extracts of ?mlrB cells detected Adda and ?mlrC cells accumulated tetrapeptide. Moreover, topology analysis of MlrB using the ß-lactamase gene fusion method insisted MlrB is the peripheral protein binding the inner-membrane. These results insist that MlrB degrades the linear microcystin in the periplasmic space and MlrC degrades tetrapeptide in cytoplasm. Thus, in intact cells, MlrC cannot degrade linear-microcystin as being separated in inner-membrane from linear-microcystin while MlrC is capable of degrading the linear-microcystin in cell-free extract

Fertilizer potential of liquid product from hydrothermal treatment of swine manure

Compared with composting, hydrothermal treatment (HTT) technology can dramatically shorten the duration for manure waste treatment. This study firstly investigated the effect of HTT on solubilization of N, P and organics from swine manure, and then evaluated the phytotoxicity of liquid product from hydrothermally treated manure by seed germination test. Results show that 98% of N in manure could be converted into soluble form after HTT at 200 °C for 60 min. Soluble P in hydrothermally treated manure (at 150 °C for 60 min) was 2.7 times that in raw manure. The germination indices (GI) were all greater than 100% when the liquid product (from HTT at 150 °C for 60 min) or its diluted samples being used. Results from this study suggest that HTT could be a promising technology for producing safe and value-added liquid fertilizers from swine manure

Seasonal change of Araskan snow cover, soil temperature and moisture - Observation of physical conditions for soil ecosystem study-

第3回極域科学シンポジウム/第35回極域気水圏シンポジウム 11月29日（木） 国立国語研究所 ２階ロビ

Arctic weather in 2012 summer and influences on Arctic Environment

第3回極域科学シンポジウム/特別セッション「これからの北極研究」11月28日（水） 国立極地研究所 2階大会議

Microbial diversity in decaying oil palm empty fruit bunch (OPEFB) and isolation of lignin degrading bacteria from tropical environment

Oil palm empty fruit bunches (OPEFB) are the most abundant, inexpensive, and environmentally friendly lignocellulosic biomass in Malaysia. Investigations on the microbial diversity of decaying OPEFB may reveal microbes with complex enzymes that have the potential to enhance the conversion of lignocellulose into second-generation biofuels as well as the production of other value-added products. In the present study, fungal and bacterial diversities in decaying OPEFB were identified using Illumina MiSeq sequencing of the V3 region of the 16S rRNA gene and V4 region of the 18S rRNA gene. Fungal diversity in decaying OPEFB was dominated by the phylum Ascomycota (14.43%), while most of the bacterial sequences retrieved belonged to Proteobacteria (76.71%). Three bacterial strains isolated from decaying OPEFB, designated as S18, S20, and S36, appeared to grow with extracted OPEFB-lignin and Kraft lignin (KL) as the sole carbon source. 16S rRNA gene sequencing identified the 3 isolates as Paenibacillus sp.. The molecular weight distribution of KL before and after degradation showed significant depolymerization when treated with bacterial strains S18, S20, and S36. The presence of low-molecular-weight lignin-related compounds, such as vanillin and 2-methoxyphenol derivatives, which were detected by a GC-MS analysis, confirmed the KL-degrading activities of isolated Paenibacillus strains