Ionic Liquid-Induced Unique Structural Transitions of Proteins

The structural transitions of proteins in aqueous solutions of various ionic liquids (ILs) over a wide concentration range (x (mol% IL) = 0–30) were investigated using Fourier-transform infrared and near-UV circular dichroism spectroscopy combined with small-angle X-ray scattering. The proteins in the aqueous IL solutions showed two structural transition patterns: (i) the folded state → unfolded state → partial globular state (α-helical formation disrupted tertiary structure) and (ii) the folded state → unfolded state → aggregation (amyloid-like aggregation or disordered aggregation). We found that the helical formation of proteins in the condensed IL solutions was strongly related to the competition between the low polarity and denaturation effect of ions. Moreover, the amyloid-like aggregate formation correlated with the competition between the size of the confined water assemblies in the IL layer and the IL-amino acid residue interactions. On the basis of these results, we discussed the future applications of ILs, including their use as cryoprotectants for proteins and as agents for the suppression of amyloid formation

High-Pressure X-ray Diffraction and Raman Spectroscopy of Ice VIII

In situ high-pressure/low-temperature synchrotron x-ray diffraction and optical Raman spectroscopy were used to examine the structural properties, equation of state, and vibrational dynamics of ice VIII. The x-ray measurements show that the pressure-volume relations remain smooth up to 23 GPa at 80 K. Although there is no evidence for structural changes to at least 14 GPa, the unit-cell axial ratio c/a undergoes changes at 10-14 GPa. Raman measurements carried out at 80 K show that the nu(Tz)A(1g)+nu Tx,yEg lattice modes for the Raman spectra of ice VIII in the lower-frequency regions (50-800 cm(-1)) disappear at around 10 GPa, and then a new peak of similar to 150 cm(-1) appears at 14 GPa. The combined data provide evidence for a transition beginning near 10 GPa. The results are consistent with recent synchrotron far-IR measurements and theoretical calculations. The decompressed phase recovered at ambient pressure transforms to low-density amorphous ice when heated to similar to 125 K.Engineering and Applied Science

酢酸摂取と運動が脂肪代謝と運動耐久性に及ぼす影響

Previously, we found that acetic acid had effects on lipid metabolism in skeletal muscles and has functions that work against obesity and obesity-linked type 2 diabetes through the activation of AMPactivated protein kinase (AMPK). During exercise, AMPK is activated in skeletal muscle according to exercise intensity and it increases fatty acid oxidation. The purpose of this study was to investigate the interactive effects of chronic intake of acetic acid and exercise training on lipid metabolism and endurance performance. Six-week-old SD rats were randomly assigned to four groups: water-injected (rest-water), acetic acid-injected (rest-ace), exercise-trained after injection of water (water-ex), and exercise-trained after injection of acetic acid (ace-ex) for 4 weeks. Body weight (BW) in rest-ace and ace-ex groups was significantly lower than rest-water group. Exercise-training groups showed an increase of exercise capacity, by the addition of intake of acetic acid, lipid oxidation was promoted during exercise tolerance test. Skeletal muscle of rats treated with acetic acid and exercise training led to higher expressions of cytochrome c (cycs), and tended to stimulate expressions of peroxisome proliferator-activated receptor coactivator 1-α (PGC1-α ) and MHC1 genes than those of rest-water group. Those results indicate that treatments both of exercise training and intake of acetic acid contribute to enhancement of lipid metabolism and improvement of exercise capacity.これまで我々は、酢酸の摂取が骨格筋内のAMP活性化プロテインキナーゼ（AMPK）の活性化を介して脂質代謝と肥満、肥満に関連した2型糖尿病の予防に効果があることを示唆してきた。AMPKは運動によって骨格筋で活性化し、脂肪酸酸化を促進する。この研究は、4週間の継続的な酢酸摂取と運動トレーニングが運動中の脂肪代謝と運動耐久性に及ぼす影響について調べることを目的とした。　6週齢のSD系雄ラットを安静期に水を摂取するrest-water群、酢酸を摂取するrest-ace群、運動前に水を摂取するwater-ex群、運動前に酢酸を摂取するace-ex群に無作為に分け実験を行った。酢酸を継続的に摂取すると水摂取に比較して腹腔内脂肪量の減少と体重増加の抑制がみられた。また継続的な酢酸摂取および運動トレーニングにより、耐久性運動下でのグルコース利用の抑制および脂肪酸酸化の促進が見られた。酢酸摂取および運動トレーニング群の腓腹筋では、MHCIおよびcytochrome c等の遅筋線維マーカー遺伝子が増加していた。継続的な酢酸摂取と運動トレーニングにより、脂肪代謝と運動耐久性の向上が示唆された

Cosmological Baryon Asymmetry in Supersymmetric Standard Models and Heavy Particle Effects

Cosmological baryon asymmetry B is studied in supersymmetric standard models, assuming the electroweak reprocessing of B and L. Only when the soft supersymmetry breaking is taken into account, B is proportional to the primordial B-L in the supersymmetric standard models. The ratio $B/(B-L)$ is found to be about one percent less than the nonsupersymmetric case. Even if the primordial B-L vanishes, scalar-leptons can be more efficient than leptons to generate B provided that mixing angles $\th$ among scalar leptons satisfy $|\th| < 10^{-8} (T/{GeV})^{1/2}$.Comment: 11 pages in LaTex, 3 PostScript figures include

Neutron Electric Dipole Moment in the Minimal Supersymmetric Standard Model

Neutron electric dipole moment (EDM) due to single quark EDM and to the transition EDM is calculated in the minimal supersymmetric standard model. Assuming that the Cabibbo-Kobayashi-Maskawa matrix at the grand unification scale is the only source of CP violation, complex phases are induced in parameters of soft supersymmetry breaking at low energies. Chargino one-loop diagram is found to give the dominant contribution of the order of $10^{-27}\sim 10^{-29}\:e\cdot$cm for quark EDM, assuming the light chargino mass and the universal scalar mass to be $50$ GeV and $100$ GeV, respectively. Therefore the neutron EDM in this class of model is difficult to measure experimentally. Gluino one-loop diagram also contributes due to the flavor changing gluino coupling. The transition EDM is found to give dominant contributions for certain parameter regions.Comment: 27 pages, LaTeX file with figures, several misprints in pp. 7, 14, 20 and 24 are correcte

Molecule Analysis of Methanogen in Siberian Permafrost

第2回極域科学シンポジウム/第33回極域生物シンポジウム 11月18日（金） 統計数理研究所 3階リフレッシュフロ