Synthesis of Short-chain-length/Medium-chain-length Polyhydroxyalkanoate (PHA) Copolymers in Peroxisome of the Transgenic Arabidopsis Thaliana Harboring the PHA Synthase Gene from Pseudomonas sp. 61-3

In this paper, the photosynthetic production of short-chain-length/medium-chain-length polyhydroxyalkanoate (PHA) copolymers is reported. The wild-type and highly active doubly mutated PHA synthase 1 (S325T/Q481K, abbreviated ST/QK) genes from Pseudomonas sp. 61-3 were introduced into Arabidopsis thaliana. Peroxisome targeting signal 1 (PTS1) was used to target PHA synthases into the peroxisome to synthesize PHA from the intermediates of the β-oxidation pathway. The transgenic Arabidopsis produced PHA copolymers consisting of 40–57 mol% 3-hydroxybutyrate, 21–49 mol% 3-hydroxyvalerate, 8–18 mol% 3-hydroxyhexanoate, and 2–8 mol% 3-hydroxyoctanoate. The maximum PHA contents were 220μ g/g cell dry weight (cdw) in leaves, and 36μ g/g cdw in stems, respectively. The expression of the ST/QK mutated PHA synthase in leaves gene did not lead to significant difference in PHA content and monomer composition of PHAs, compared to the wild-type PHA synthase gene, suggesting that the supply of monomers may be a rate-determining step of PHA biosynthesis in the peroxisome. However, in stems, there were significant differences dependent on whether the wild-type or ST/QK mutated PHA synthase was expressed. These results suggest that tissue-specific monomer availability is important in determining the final mol% composition of PHA copolymers produced by the peroxisome in plants.     

Effect of different soil layers on porewater to remediate acidic surface environment at a close mine site

This paper describes the chemistry of porewater when constructing different soil layers on acidic weathered rock of a closed mine to remediate the surface environment. Three cases were set on a flat surface of the site, all under different layer systems. Case 1 was only composed of weathered rocks. A top neutralization layer was constructed on the weathered rocks in case 2, whereas both an upper low-permeable and middle neutralization layers were constructed on the weathered rocks in case 3. The low-permeable layer of 30?cm thick consists of clay, and the neutralization layer of 30?cm thick consists of the mixture of the weathered rock and calcium carbonate as a neutralizer. Porewater sampling systems and soil sensors to measure temperature, water content, and electrical conductivity were set at different depths. In case 1, steadily high concentrations of heavy metals were observed regardless of the depth, and the pH ranged from 2 to 4. In cases 2 and 3, a dramatic decrease in concentrations of heavy metals was observed, even below the neutralization layer. For both cases, pH values were circumneutral. There were no significant seasonable changes in heavy metals concentrations and pH of porewater by considering the temperature and precipitation. In addition, the water content of the layers in case 3 fluctuated more mildly than that in cases 1 and 2, indicating that the low-permeable layer reduced the rate of infiltration. Therefore, a significant reduction in the load of heavy metals released from the site can be achieved by both implementing neutralization and low-permeable layers.     

New energy policy and low-carbon society in Japan after the Great East Japan Earthquake

The Great East Japan Earthquake in March 2011 devastated the eastern region of Japan.Due to the resulting nuclear accident,Japanese Cabinet decided to revise its energy policies.The Energy and Environment Council in National Policy Unit published options on the nation’s scenarios for energy and economy in 2030.We estimated the economic impacts of the options to national economy and households in 2030.Finally,we clarified significant factors to establish a secure,affluent and low-carbon society based on the energy scenarios.     

Investigating potential for effects of environmental endocrine disrupters on wild populations of amphibians in UK and Japan: status of historical databases and review of methods.

Concern over global declines among amphibians has resulted in increased interest in the effects of environmental contaminants on amphibian populations, and more recently, this has stimulated research on the potential adverse effects of environmental endocrine disrupters in amphibians. Laboratory studies of the effects of single chemicals on endocrine-relevant endpoints in amphibian, mainly anuran, models are valuable in characterizing sensitivity at the individual level and may yield useful bioassays for screening chemicals for endocrine toxicity (for example, thyroid disrupting activity). Nevertheless, in the UK and Japan as in many other countries, it has yet to be demonstrated unequivocally that the exposure of native amphibians to endocrine disrupting environmental contaminants results in adverse effects at the population level. Assessing the potential of such effects is likely to require an ecoepidemiological approach to investigate associations between predicted or actual exposure of amphibians to (endocrine disrupting) environmental contaminants and biologically meaningful responses at the population level. In turn, this demands recent but relatively long-term population trend data. We review two potential sources of such data for widespread UK anurans that could be used in such investigations: records for common frogs and common toads in several databases maintained by the Biological Records Centre (UK Government Centre for Ecology and Hydrology), and adult toad count data from 'Toads on Roads' schemes registered with the UK wildlife charity 'Froglife'. There were little abundance data in the BRC databases that could be used for this purpose, while count data from the Toads on Roads schemes is potentially confounded by the effects of local topology on the detection probabilities and operation of nonchemical anthropogenic stressors. For Japan, local and regional surveys of amphibians and national ecological censuses gathering amphibian data were reviewed to compile survey methodologies and these were compared with methods used in the UK and other countries. Substantial consensus exists in amphibian survey methodologies and this should be exploited in the initiation of coordinated monitoring programs for widespread and common anuran amphibians in Japan and the UK to generate long-term robust and standardized population trend data. Such data would support comparative ecoepidemiological assessments of the impact of environmental endocrine disrupters in these two cooperating countries.     

Evaluation of activated carbon fiber filter for sampling of organochlorine pesticides in environmental water samples

A simple method for quantitative analyses of organic chlorine pesticides (OCPs) in environmental water samples such as rainwater, river water and seawater using activated carbon fiber filters (ACFF) is described. ACFF was used as adsorbent to collect the chemicals in water samples. The collection of OCPs was completed almost for one day by stirring the mixture of the sample and the ACFF chips at room temperature. The adsorbed OCPs on the ACFF could be extracted easily with toluene-ethanol (4:1) mixed solvent. The purified extract by a florisil column chromatograph was followed by the analysis using high-resolution gas chromatograph/high-resolution mass spectrometer. Recoveries of OCPs spiked to actual samples such as rainwater, river water and seawater samples were approximately more than 80%, and the coefficients of variations were within 10%. This method was applied to the actual samples and was confirmed to be applicable for monitoring sub-ng/l level OCPs in environmental water samples.     

Procurement of exogenous ammonia by the swallowtail butterfly, Papilio polytes, for protein biosynthesis and sperm production

How to acquire sufficient quantity of nitrogen is a pivotal issue for herbivores, particularly for lepidopterans (butterflies and moths) of which diet quality greatly differs among their life stages. Male Lepidoptera often feed from mud puddles, dung, and carrion, a behavior known as puddling, which is thought to be supplementary feeding targeted chiefly at sodium. During copulation, males transfer a spermatophore to females that contains, besides sperm, nutrients (nuptial gifts) rich in sodium, proteins, and amino acids. However, it is still poorly understood how adults, mostly nectarivores, extract nitrogen from the environment. We examined the availability of two ubiquitous inorganic nitrogenous ions in nature, viz. ammonium (or ammonia) and nitrate ions, as nutrients in a butterfly, and show that exogenous ammonia ingested by adult males of the swallowtail, Papilio polytes, can serve as a resource for protein biosynthesis. Feeding experiments with ¹⁵N-labeled ammonium chloride revealed that nitrogen was incorporated into eupyrene spermatozoa, seminal protein, and thoracic muscle. Ammonia uptake by males significantly increased the number of eupyrene sperms in the reproductive tract tissues. The females also had the capacity to assimilate ammonia into egg protein. Consequently, it is evident that acquired ammonia is utilized for the replenishment of proteins allocable for reproduction and somatic maintenance. The active exploitation of exogenous ammonia as a nutrient by a butterfly would foster better understanding of the foraging and reproductive strategies in insects.     

Seasonal change of persistent organic pollutant concentrations in air at Niigata area,Japan

The concentrations of persistent organic pollutants (POPs), such as HCB, alpha-, beta-, gamma- and delta-HCH, trans- and cis-chlordane (t-CHL, c-CHL), DDE, DDD and DDT, in ambient air have been measured at five sampling points in Niigata area, Japan (Niigata, Maki, Tsubame, Jouzo and Yahiko) during the period from September 1999 to November 2001. HCB, alpha-HCH, t-CHL and c-CHL showed higher concentrations than the other chemicals in all locations. All the POPs except t-CHL and c-CHL collected at urban sites of the Niigata Plain was almost the same in their concentration levels. Higher concentrations of t-CHL and c-CHL in residential areas should be attributed to the past usage of the chemical as a termiticide. At Yahiko (remote site), most of the POPs showed lower concentrations than those measured at the other sampling sites, although alpha-HCH and gamma-HCH were comparable with the concentrations found at the other sampling sites. All POPs except alpha-HCH and gamma-HCH tend to decrease 41-80% in their concentrations from 2000 to 2001. The lower POPs concentrations in winter and the higher POPs concentrations in summer at every sampling point can be partly explained by temperature differences. Applying the equation of the logarithm of the POP partial pressure in air versus reciprocal temperature (lnPa=m/T+b) to our data, linear relations were observed. HCB gave a poor linearity and the smallest slope, while beta-HCH, t-CHL and c-CHL gave good linearities and large slopes in the equation. The results suggest that HCB level is influenced by not only the emission from terrestrial sources but the global-scale background pollution. A peculiar observation is that beta-HCH concentration measured in our study showed large temperature dependence, indicating there could be a source of contamination in the surrounding areas.