月別: 2017年2月

[Published online Journal of Computer Chemistry, Japan Vol.15, 239-241, by J-STAGE]
<Title:> Electronic Similarity among Protein-Ligand Complexes: Development of the Interaction-Energy Projection Method
<Author(s):> Manabu SUGIMOTO, Takafumi INOUE
<Corresponding author E-Mill:> sugimoto(at)kumamoto-u.ac.jp
<Abstract:> A numerical model, called the interaction energy projection method (IEPM), is suggested to evaluate electronic similarity among protein-ligand complexes. Herein we apply the method by referring to the “inter-fragment interaction energy (IFIE),” calculated using the fragment molecular orbital (FMO) method, in two human estrogen receptor complexes.
<Keywords:> Electronic similarity, Protein-ligand docking, Fragment molecular orbital method, Inter-fragment interaction energy, Estrogen receptor, Interaction energy projection method
<URL:> https://www.jstage.jst.go.jp/article/jccj/15/6/15_2016-0061/_article/-char/ja/

[Published online Journal of Computer Chemistry, Japan Vol.15, 242-244, by J-STAGE]
<Title:> What Activates the Nitrogen Molecule in Ammonia Synthesis Using Supported Metal Catalysts ? A Quantum-Chemical Model Study
<Author(s):> Manabu SUGIMOTO
<Corresponding author E-Mill:> sugimoto(at)kumamoto-u.ac.jp
<Abstract:> The N-N bond breaking of the N₂ molecule on a metal surface is the key process in the ammonia synthesis using heterogeneous catalysts. Herein we discuss electronic factors in the bond cleavage on the basis of electronic-structure calculations. It is shown that the hydrogenation of the end-on coordinated N₂ molecule may play an important role, which may be accompanied by electron transfer from the catalyst to N₂.
<Keywords:> Electronic-structure calculations, Ammonia synthesis, Catalysis, Supported metal catalyst, Surface adsorption
<URL:> https://www.jstage.jst.go.jp/article/jccj/15/6/15_2016-0062/_article/-char/ja/

[Published online Journal of Computer Chemistry, Japan Vol.15, 235-238, by J-STAGE]
<Title:> フタロシアニン フラーレン系における電子物性評価
<Author(s):> 光井　和輝, 池永　祐乙, 成島　和男, 高　緑
<Corresponding author E-Mill:> narushim(at)ube-k.ac.jp
<Abstract:> Recently, studies of solar cells have been conducted actively. Especially, organic thin film solar cells are attracting attention for use as a next-generation flexible substrate material. The reasons include the recent advent of bulk heterojunction structures. Nevertheless, bulk heterojunction solar cells exhibit only about 10% conversion efficiency. They have remained in the study phase. One reason for their low conversion efficiency is that a bulk heterojunction conductive mechanism is so complicated that its fundamental electronic properties have not been elucidated well. This letter describes an examination of the excited state of the bulk heterojunction structure and evaluates its electronic properties. Charge densities are computed for excited and ground states. Then absorbance is computed and examined. Results suggest that the electronically excited state might come to differ from the electronic ground state in a phthalocyanine fullerene bimolecular system. Moreover, we infer that this behavior brings about energy level change and subsequent variation in absorbance.
<Keywords:> Bulk Hetero Junction, Organic thin Film Solar Cell, Molecular Orbital Method, Density Functional Method, Charge Density, Absorbance
<URL:> https://www.jstage.jst.go.jp/article/jccj/15/6/15_2016-0065/_article/-char/ja/

[Published online Journal of Computer Chemistry, Japan Vol.15, A52-A54, by J-STAGE]
<Title:> Special Contribution to The Quantum Hydrogen Issue of Journal of Computer Chemistry, Japan
<Author(s):> Yasuyuki ISHIKAWA
<Corresponding author E-Mill:> yasuyukiishikawa1(at)gmail.com
<Abstract:>
<Keywords:>
<URL:> https://www.jstage.jst.go.jp/article/jccj/15/5/15_Special_Contribution_15_5/_article/-char/ja/

[Published online Journal of Computer Chemistry, Japan Vol.15, 229-231, by J-STAGE]
<Title:> Investigation of a Virtual Nested Two-dimensional Lattice Model for Representing the Diffusive Motion of a Transmembrane Protein in Cell Membrane
<Author(s):> Atsushi OKUMOTO, Tomonari SUMI, Hideo SEKINO, Hitoshi GOTO
<Corresponding author E-Mill:> gotoh(at)tut.jp
<Abstract:> As a refinement of the fluid mosaic model for explaining cell membrane functions, membrane-skeleton fence model and anchored membrane protein picket model have been proposed according to the tracing experiment of a single molecule in plasma membrane. In addition, the experimental observation that the diffusive motion of a transmembrane protein in plasma membrane leads to a normal diffusion through two-step relaxation has suggested that there are two types of nested compartments, large and small. In this paper, we propose a virtual nested two-dimensional lattice model that can express a nested compartment structure of plasma membrane using three parameters in order to represent such a single molecule diffusion movement. Using this 2D lattice model, various diffusive motion simulations of one particle random walks were performed and their trajectories were analyzed by Detrended fluctuation analysis. As a result, we have confirmed that both plasma membrane models, “fence” and “picket,” can be represented by our virtual nested 2D lattice model.
<Keywords:> Transmembrane protein, Plasma membrane, Diffusion movement, Random walk, Detrended fluctuation analysis
<URL:> https://www.jstage.jst.go.jp/article/jccj/15/6/15_2016-0069/_article/-char/ja/

[Published online Journal of Computer Chemistry, Japan Vol.15, 232-233, by J-STAGE]
<Title:> 計算化学による生体分子の結合，運搬，代謝の機構解明
<Author(s):> 河野　雅弘, 畠山　望, 蒲池　利章, 宮本　明
<Corresponding author E-Mill:> kohno.m.aa(at)m.titech.ac.jp
<Abstract:> The existence of an energy field that dominates the physiological mechanism of incorporating O₂ in the atmosphere into the human body and excreting it outside the body as CO₂ was investigated using computational chemistry techniques based on quantum theory. As a result, it was revealed that the binding, transportation, and metabolism of gas molecules depend on the weak magnetic energy induced by the earth’s magnetic field (H₀ = 4.5 × 10^-5 T). Finally, it was concluded that the mechanism of oxygen transport and Christian Bohr’s proposed”Bohr effect” depend on magnetic coupling between biomolecules.
<Keywords:> Magnetic resonance, Hemoglobin, Myoglobin, Oxygen, Carbon dioxide
<URL:> https://www.jstage.jst.go.jp/article/jccj/15/6/15_2016-0059/_article/-char/ja/

[Published online Journal of Computer Chemistry, Japan Vol.15, 227-228, by J-STAGE]
<Title:> スマートフォンを用いたSPM可視化アプリケーションの開発
<Author(s):> 八木　徹, 神部　順子, 長嶋　雲兵, 青山　智夫
<Abstract:> A smartphone application for observating atmospheric state and visualizing suspended particle matter (SPM) was developed. By using the ratio of B/R, G/R and B/G, it was confirmed that the nonlinearity in the developed image can be canceled and the distribution of scattered light in the atmosphere can be observed.
<Keywords:> SPM, Smartphone application, Visualization, Scattered light, Air polution
<URL:> https://www.jstage.jst.go.jp/article/jccj/15/6/15_2016-0063/_article/-char/ja/