Faculty of Frontiers of Innovative Research in Science and Technology

Papers -

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Development of a CaCO3 Precipitation Method Using a Peptide and Microwaves Generated by a Magnetron Reviewed

Fumihiro Kayamori Hiroyuki Togashi Natsumi Endo Makoto Ozaki Kan Hirao Yonejiro Arimoto Ryuji Osawa Takaaki Tsuruoka Takahito Imai Kin-ya Tomizaki Tomohiro Umetani Nobuhiro Nakanishi Kenji Usui

Processes 12 ( 7 ) 1327 2024.6

Microwave applications, such as microwave ovens and mobile phones, are ubiquitous and indispensable in modern society. As the utilization of microwave technology is becoming more widespread, the effects of microwaves on living organisms and physiological processes have received increased attention. This study aimed to investigate the effects of microwaves on calcium carbonate biomineralization as a model biochemical process. A magnetron oscillator was used to generate 2450 MHz microwaves because magnetrons are relatively inexpensive and widespread. We conducted transmission electron microscopy (TEM), atomic force microscopy (AFM), TEM-electron energy-loss spectroscopy (EELS), dynamic light scattering (DLS), and high-performance liquid chromatography (HPLC) measurements to analyze the calcium carbonate precipitates. Our findings showed the formation of string-like precipitates of calcium carbonate upon microwave irradiation from one direction, similar to those obtained using a semiconductor oscillator, as reported previously. This implied that the distribution of the frequency had little effect on the morphology. Furthermore, spherical precipitates were obtained upon microwave irradiation from two directions, indicating that the morphology could be controlled by varying the direction of microwave irradiation. Magnetrons are versatile and also used in large-scale production; thus, this method has potential in medical and industrial applications.

Inhibition of RNA phosphodiester backbone cleavage in the presence of organic cations of different sizes Invited Reviewed International journal

S. Yoshioka, A. Doi, and S. Nakano

ChemBioChem 25 ( 13 ) e202400276 2024.5

Joint Work

Authorship：Last author,　Corresponding author Publisher：Wiley

Living cells contain various types of organic cations that may interact with nucleic acids. In order to understand the nucleic acid–binding properties of organic cations of different sizes, we investigated the ability of simple organic cations to inhibit the RNA phosphodiester bond cleavage promoted by Mg2+, Pb2+, and RNA-cleaving serum proteins. Kinetic analysis using chimeric DNA–RNA oligonucleotides showed that the cleavage at ribonucleotide sites was inhibited in the presence of monovalent cations comprising alkyl chains or benzene rings. The comparison of the cleavage rates in the presence of quaternary ammonium and phosphonium ions indicated that the steric hindrance effect of organic cations on their binding to the RNA backbone is significant when the cation size is larger than the phosphate–phosphate distance of a single-stranded nucleic acid. The cleavage inhibition was also observed for ribonucleotides located in long loops but not in short loops of oligonucleotide structures, indicating less efficient binding of bulky cations to structurally constrained regions. These results reveal the unique nucleic acid–binding properties of bulky cations distinct from those of metal ions.

DOI： 10.1002/cbic.202400276.

Interfacial analysis of the ion-transport process controlling the steady-state current in a two-phase electrodeposition system using polyelectrolyte membranes Reviewed

Shunsuke Yamada, Yohei Takashima, Takaaki Tsuruoka, Kensuke Akamatsu

RSC Appl. Interfaces 1 1069 - 1076 2024.5

細胞内環境で安定化する核酸構造を標的にした低分子薬の開発 Invited

橋本佳樹, 川内敬子, 三好大輔

MEDCHEM NEWS (日本薬学会） 34 ( 1 ) 36 - 42 2024.4

Authorship：Corresponding author

DOI： 10.14894/medchem.34.1_36

Separation of the diastereomers of phosphorothioated siRNAs by anion-exchange chromatography under non-denaturing conditions Reviewed

Hiroyuki Togawa, Takashi Okubo, Kazuki Horiuchi, Takao Yamaguchi, Elisa Tomita-Sudo, Tomoka Akita, Junji Kawakami, Satoshi Obika

Journal of Chromatography A 1721 464847 - 464847 2024.4

Publisher：Elsevier BV

DOI： 10.1016/j.chroma.2024.464847

Basic protein- and peptide-induced stabilization of long-loop DNA G-quadruplexes Reviewed International journal

K. Tanabe, K. Miyazaki, H. Umeno, M. Takemoto, and S. Nakano

Biochimie 219 110 - 117 2024.4

Joint Work

Authorship：Last author,　Corresponding author Publisher：Elsevier

The human genome contains many G-quadruplex-forming sequences, including sequences containing long single-stranded loops that are believed to be unfavorable for G-quadruplex formation. The intracellular environment of biological cells is crowded with proteins with charged surfaces. Understanding the effects of protein-rich environments is important for understanding the formation of G-quadruplexes in an intracellular environment. In this study, we investigated the structural stability of DNA G-quadruplexes in the presence of several types of globular proteins (lysozyme, cytochrome c, bovine serum albumin, myoglobin, histone proteins, and serum proteins), unstructured polypeptides (protamine and poly-l-lysine), and oligopeptides (RGG/RG-domain peptides and short repeated peptides). Thermal melting studies of G-quadruplex-forming oligonucleotides derived from the human telomeric repeat sequence revealed that environments containing high concentrations of proteins and peptides differently affected the G-quadruplex stability according to their loop lengths. We found that weak electrostatic interactions of G-quadruplex loops with basic proteins and peptides improved the stability of long-loop G-quadruplexes and the interactions were strengthened under crowded conditions simulated by dextran. The comparison of the effects of different types of proteins and peptides indicated that excluded volume interactions and structural flexibility of both DNA and polypeptide chains influenced the efficiency of their interactions. This study provides insights into long-loop G-quadruplex stability in a crowded intracellular environment and the recognition of G-quadruplexes by arginine-rich domains of G-quadruplex-binding proteins.

DOI： 10.1016/j.biochi.2023.11.005

Development of a Pseudocellular System to Quantify Specific Interactions Determining the G-Quadruplex Function in Cells Reviewed

Hisae Tateishi-Karimata, Keiko Kawauchi, Shuntaro Takahashi, Naoki Sugimoto

Journal of the American Chemical Society 146 ( 12 ) 8005 - 8015 2024.3

Publisher：American Chemical Society (ACS)

DOI： 10.1021/jacs.3c11160

Cr(NO<sub>3</sub>)<sub>3</sub> as a New Etching Reagent for an Al-Based Metal–Organic Framework to Control Its Crystal Size and Defects Reviewed

Yohei Takashima, Naoto Tanabe, Shintaro Tanaka, Takaaki Tsuruoka, Kensuke Akamatsu

Crystal Growth & Design 24 ( 4 ) 1766 - 1773 2024.2

Publisher：American Chemical Society (ACS)

DOI： 10.1021/acs.cgd.3c01405

Cr(NO3)3 as a new etching reagent for an Al-based metal-organic framework to control its crystal size and defects Reviewed

Yohei Takashima, Naoto Tanabe, Shintaro Tanaka, Takaaki Tsuruoka, Kensuke Akamatsu

Cryst. Growth Des. 24 1766 - 1773 2024.2

Authorship：Lead author,　Corresponding author

Structure and thermoelectric characterization of p-Type SnTe nanobulk material synthesized by charge compensation chemical reaction Reviewed

Ryosuke Fujiwara, Yuta Ikeda, Takuto Kawaguchi, Yohei Takashima, Takaaki Tsuruoka, Kensuke Akamatsu

Energies 17 190 2024.2

Inhibitory Effects of Shikonin Dispersion, an Extract of Lithospermum erythrorhizon Encapsulated in β-1,3-1,6 Glucan, on Streptococcus mutans and Non-Mutans Streptococci Reviewed

Ryota Nomura, Yuto Suehiro, Fumikazu Tojo, Saaya Matayoshi, Rena Okawa, Masakazu Hamada, Shuhei Naka, Michiyo Matsumoto-Nakano, Rika Unesaki, Kazuya Koumoto, Keiko Kawauchi, Takahito Nishikata, Tatsuya Akitomo, Chieko Mitsuhata, Masatoshi Yagi, Toshiro Mizoguchi, Koki Fujikawa, Taizo Taniguchi and Kazuhiko Nakano

25 1075 2024.1

Inhibitory Effects of Shikonin Dispersion, an Extract of Lithospermum erythrorhizon Encapsulated in β -1,3-1,6 Glucan, on Streptococcus mutans and Non-Mutans Streptococci Reviewed

Nomura R, Suehiro Y, Tojo F, Matayoshi S, Okawa R, Hamada M, Naka S, Matsumoto-Nakano M, Unesaki R, Koumoto K, Kawauchi K, Nishikata T, Akitomo T, Mitsuhata C, Yagi M, Mizoguchi T, Fujikawa K, Taniguchi T, Nakano K

International Journal of Molecular Science 25 1075 2024.1

Joint Work

DOI： doi.org/10.3390/ijms25021075

Inhibitory Effects of Shikonin Dispersion, an Extract of Lithospermum erythrorhizon Encapsulated in β-1,3-1,6 Glucan, on Streptococcus mutans and Non-Mutans Streptococci. Reviewed International journal

International journal of molecular sciences 25 ( 2 ) 2024.1

Shikonin is extracted from the roots of Lithospermum erythrorhizon, and shikonin extracts have been shown to have inhibitory effects on several bacteria. However, shikonin extracts are difficult to formulate because of their poor water solubility. In the present study, we prepared a shikonin dispersion, which was solubilized by the inclusion of β-1,3-1,6 glucan, and analysed the inhibitory effects of this dispersion on Streptococcus mutans and non-mutans streptococci. The shikonin dispersion showed pronounced anti-S. mutans activity, and inhibited growth of and biofilm formation by this bacterium. The shikonin dispersion also showed antimicrobial and antiproliferative effects against non-mutans streptococci. In addition, a clinical trial was conducted in which 20 subjects were asked to brush their teeth for 1 week using either shikonin dispersion-containing or non-containing toothpaste, respectively. The shikonin-containing toothpaste decreased the number of S. mutans in the oral cavity, while no such effect was observed after the use of the shikonin-free toothpaste. These results suggest that shikonin dispersion has an inhibitory effect on S. mutans and non-mutans streptococci, and toothpaste containing shikonin dispersion may be effective in preventing dental caries.

DOI： 10.3390/ijms25021075

PubMed

Direct Formation of ZIF-8 Crystal Thin Films on the Surface of a Zinc Ion-Doped Polymer Substrate Reviewed

Takaaki Tsuruoka, Kaito Araki, Kouga Kawauchi, Yohei Takashima, Kensuke Akamatsu

Inorganics 12 ( 1 ) 21 - 21 2024.1

Authorship：Lead author,　Corresponding author Publisher：MDPI AG

Thin films of metal–organic frameworks (MOFs) on polymer substrates and MOF/polymer mixed-matrix membranes play crucial roles in advancing the field of gas separation membranes. In this paper, we present a novel method for the direct formation of continuous ZIF-8 crystal films on a polymer substrate doped with Zn²+. Our approach involves ion exchange between the doped zinc ions within the substrate and sodium ions in the presence of a CH3COONa additive, as well as interfacial complexation with eluted zinc ions and 2-methylimidazole (2-MeIM). The key factors affecting the formation of ZIF-8 crystals on the substrate were the concentrations of CH3COONa and 2-MeIM. A time-course analysis revealed that the nucleation rate during the early stages of the reaction significantly affected the surface morphology of the resulting ZIF-8 crystal films. Specifically, a higher nucleation rate led to the formation of continuous small ZIF-8 crystal films. This innovative approach enables the fabrication of densely packed, uniform ZIF-8 crystal films.

DOI： 10.3390/inorganics12010021

Direct formation of ZIF-8 crystal thin films on the surface of a zinc ion-doped polymer substrate Reviewed

Takaaki Tsuruoka, Kaito Araki, Kouga Kawauchi, Yohei Takashima, Kensuke Akamatsu

Inorganics 12 21 2024.1

“Interfacial analysis of the ion-transport process controlling the steady-state current in a two-phase electrodeposition system using polyelectrolyte membranes Reviewed

S. Yamada, Y. Takashima, T. Tsuruoka, K. Akamatsu

RSC Applied Interfaces 2024

Authorship：Corresponding author

Structural transformation of silver(I)-thiolate coordination polymer film at solid–liquid interfaces Reviewed

M. Fukuoka, Y. Takashima, K. Akamatsu, A. Demessence, T. Tsuruoka

CrystEngComm 26 6269 - 6273 2024

Preparation of golf ball-like polymer particles bearing site-selective functional groups Reviewed

T. Morishita, I. Maitani, T. Michiura, N. Suzuki, T. Suzuki, K. Akamatsu, H. Minami

ACS Appl. Mater.Interfaces in press 2024

Structure and Thermoelectric Characterization of p-Type SnTe Nanobulk Material Synthesized by Charge Compensation Chemical Reaction Reviewed

Ryosuke Fujiwara, Yuta Ikeda, Takuto Kawaguchi, Yohei Takashima , Takaaki Tsuruoka and Kensuke Akamatsu

Energies 17 ( 190 ) 2024

Authorship：Corresponding author

Cr(NO3)3 as a New Etching Reagent for an Al-based Metal-Organic Framework to Control Its Crystal Size and Defects Reviewed

Y. Takashima, N. Tanabe, S. Tanaka, T. Tsuruoka, K. Akamatsu

Cryst. Growth Des 24 1766 - 1773 2024

Authorship：Last author

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