研究者詳細 - 浅沼　浩之

論文 - 浅沼　浩之

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2¢,6¢-Dimethylazobenzene as an efficient and thermo-stable photo-regulator for the photoregulation of DNA hybridization 査読有り

Hidenori Nishioka, Xingguo Liang, Hiromu Kashida, and Hiroyuki Asanuma

Chem. Commun. 2007 巻頁： 4354-4356 2007年

Recognition of Solution Structures of Peptides byMolecularly Imprinted Cyclodextrin Polymers 査読有り

Shi-hui Song, Kazumi Shirasaka, Mami Katayama,Suguru Nagaoka, Shinji Yoshihara, Tomo Osawa,Jun Sumaoka, Hiroyuki Asanuma, andMakoto Komiyama

Macromolecules 40 巻頁： 3530-3532 2007年

Construction of novel dye aggregates based on "comb-type" sequence

Hiromu Kashida, Taiga Fujii, Hiroyuki Asanuma

Nucleic Acids Symp. Ser. 51 巻頁： 11-12 2007年

担当区分：筆頭著者記述言語：英語

Novel dye aggregates (“comb-type" aggregates) was prepared by hybridizing modified oligodeoxyribo-nucleotides (ODNs), in which dyes were introduced consecutively. From NMR structural analysis, dye molecules were intercalated between base pairs and stacked in anti-parallel manner. When ODNs containing three Methyl Red moieties were hybridized, strong exciton coupling was observed. In addition, thermal stability of duplex was substantially enhanced due to the intermolecular stacking.

Covalent Incorporation of Methyl Red Dyes into Double-Stranded DNA for Their Ordered Clustering 査読有り

Kashida, H.; Tanaka, M.; Baba, S.; Sakamoto, T.; Kawai, G.; Asanuma, H.; Komiyama, M.

Chem. Eur. J. 12 巻頁： 777-784 2006年

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

Ordered dye cluster of Methyl Reds was formed in double-stranded DNA by hybridizing two complementary DNA-dye conjugates that involve Methyl Red moiety on threoninol linker and 1,3-propanediol as a spacer alternately in the middle of the sequence. In the duplex, Methyl Reds from each strand were axially stacked anti-parallel to each other as determined from NMR analysis. This clustering of Methyl Reds induced distinct change of both UV-Vis and CD spectra. Single-stranded DNA-Methyl Red conjugate on D-threoninol linkers and (1,3-propanediol) spacers exhibited broad absorption spectrum having lmax at around 480 nm, and almost no CD was observed at around absorption maximum of Methyl Red. However, when Methyl Reds were clustered by hybridization, lmax shifted towards shorter wavelength with respect to its monomeric transition. This hypsochromic shift increased with the number of Methyl Reds. Furthermore, positive couplet was also strongly induced here. These dye clusters are H-aggregates, in which molecular excitons are coupled. The positive couplet demonstrates that the clusters on D-threoninol forms right-hand helix. In contrast, induced CD became much weaker with Methyl Red on L-threoninol, which intrinsically prefers counterclockwise winding. Thus, mutual orientation of the stacked dyes was controlled by the chirality of the linker.

Incorporation of methyl group on azobenzene for the effective photo-regulation of hybridization and suppression of thermal isomerization

H. Nishioka, H. Kashida, M. Komiyama, X. Liang, and H. Asanuma

Nucleic Acids Res. Supple. 50 巻頁： 85-86 2006年

Activation of DNA enzyme 10-23 by tethering an intercalator to its backbone

H. Hayashi, X. Liang, J. Zhao, M. Komiyama, and H. Asanuma

Nucleic Acids Res. Supple 50 巻頁： 167-168 2006年

Enhancement of RNA cleavage activity of 10-23 DNAzyme by covalently introduced intercalator 査読有り

H. Asanuma, H. Hayashi, J. Zhao, X. Liang, A. Yamazawa, T. Kuramochi, D. Matsunaga, Y. Aiba, H. Kashida, M. Komiyama

Chem. Commun. 頁： 5062-5064 2006年

Azobenzene-tethered T7 promoter for Efficient Photoregulation of Transcription 査読有り

Minghe Liu, Hiroyuki Asanuma, Makoto Komiyama

J. Am. Chem. Soc. 128 巻頁： 1009-1015 2006年

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

Azobenzene was additionally introduced into side chain of T7 promoter for the photoregulation of transcription reaction by T7 RNA polymerase (T7 RNAP). When single azobenzene molecule was introduced into the T7 promoter either at the loop binding region of the RNAP (–7 to –11 position) or at the unwinding region (+1 to –4 position), transcription was suppressed in the trans-form but proceeded faster in the cis-form. The amount of transcripts after UV irradiation with respect to that under dark was only 1.5 – 2.0-fold. Kinetic analysis of the transcription reaction revealed that photoregulatory mechanism was different in these positions. The photoisomerization of an azobenzene at the loop binding region primarily affected Km. On the other hand, the isomerization of an azobenzene at unwinding region mainly affected kcat. Still more clear-cut photoregulation was achieved when two azobenzenes were introduced into both loop binding and unwinding regions, respectively: transcription proceeded 7.6-fold faster after UV irradiation than that under dark. This synergistic effect was observed only when two azobenzenes were introduced into these two different regions, respectively, and introduction into the same loop binding region drastically lowered the transcription activity. The cooperation of two azobenzenes at loop binding and unwinding region would contribute to the clear-cut photoregulation of transcription.

Importance of the Position of Vinyl Group on b-Cyclodextrin for the Effective Imprinting of Amino Acid Derivatives and Oligopeptides in Water 査読有り

Osawa, T.; Shirasaka, K.; Matsui, T.; Akiyama, T.; Yoshihara, S.; Hishiya, T.; Asanuma, H.; Komiyama, M.

Macromolecules 39 巻頁： 2460-2466 2006年

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

Two kinds of vinyl monomers of b-cyclodextrin (b-CyD) that tether a vinyl group on either wider rim of the truncated cone or its smaller rim were synthesized and applied to the imprinting towards amino acid derivatives and oligopeptides in water. Mono-3-(N-acrylamido)-3-deoxy-altro-b-cyclodextrin (3-AAm-CyD) showed remarkable imprinting effect for the enantioselective recognition of protected amino acids such as N-benzyloxycarbonyltyrosine (Z-Tyr). However, the imprinted polymer from mono-6-(N-acrylamido)-6-deoxy-b-cyclodextrin (6-AAm-CyD) hardly showed enantioselectivity. According to NOESY analysis on pre-organized b-CyD/Z-Tyr complex in D2O, the aromatic moieties of Z-Tyr were included into the cavity of b-CyD from its wider rim. Since the vinyl group of 3-AAm-CyD protruded towards the template and was polymerized there, detailed shape of the template was precisely copied on the polymer by the imprinting. In case of 6-AAm-CyD, however, the shape of template could not be well transcribed because its vinyl group was located at opposite side of the cavity and thus co-polymerization occurred far from the template molecule. On the other hand, the imprinted polymers from both b-CyD vinyl monomers were effective for the recognition of sequences of tetrapeptides composed of two glycines and two phenylalanines, although the selectivity itself was not remarkable. In these polymers, even the b-CyD residues of 6-AAm-CyD were immobilized complementarily to the phenyl rings and bound them.

Improved Method of Molecular Imprinting of Cyclodextrin on Silica-gel Surface for the Preparation of Stable Stationary HPLC Phase 査読有り

Matsui, T. , Osawa , T.; Shirasaka , K.; Katayama, M.; Hishiya, T.; Asanuma H., Komiyama, M.

J. Inclu. Phenom. Macrocyclic Chem. 56 巻頁： 39-44 2006年

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

By using N-(3-triethoxysilyl)propylacrylamide (TPAAm), vinyl groups were introduced onto the surface of silicagel.
On the surface of this silica-gel, b-CyD was molecularly imprinted by using a redox initiator, and the composite
was used as stationary phase of high performance liquid chromatography (HPLC). The pump pressure was sufficiently
low and did not increase even after continuous elution for 24 h. In order to prepare still more stable columns,
a new polymerization process was developed. There, the redox initiator was first mixed with the surface-modified
silica-gel and then vinylated b-CyD, crosslinker, and the template were added. This modification promoted the
immobilization of b-CyD copolymer to the silica-gel, resulting in still lower pump pressure. Concurrently, the
imprinting efficiency was increased in comparison with previous method where the redox initiator was directly
added to the mixture of the b-CyD–template complex, crosslinker, and surface-modified silica-gel. The molecularly
imprinted b-CyD column, prepared by this new method, efficiently discriminated the enantiomers of
N-benzyloxycarbonyltyrosine.

Exciplex Formation between Pyrene and N,N-Dimethylaniline in DNA for the Detection of One-base Deletion 査読有り

Hiromu Kashida, Makoto Komiyama, Hiroyuki Asanuma

Chem. Lett. 35 巻 ( 8 ) 頁： 934-935 2006年

Insertion of Two Pyrene Moieties to Oligodeoxyribonucleotides for the Efficient Detection of Insertion/Deletion Polymorphisms 査読有り

Hiromu Kashida, Hiroyuki Asanuma, Makoto Komiyama

Chem. Commun. 頁： 2768-2770 2006年

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

For the detection of deletion polymorphisms, two pyrene moieties are tethered to oligodeoxyribonucleotide (ODN) on both sides of the intervening base. When this probe ODN was hybridized with wild type ODN, both pyrenes intercalated between base pairs and only monomer emission was observed. In contrast, strong excimer emission was generated by hybridization with one-base deletion mutant. Similarly, two-base deletion was also detected.

Clear-cut photo-regulation of the formation and dissociation of the DNA duplex by modified oligonucleotide involving multiple azobenzenes

Hiroyuki Asanuma, Daijiro Matsunaga, Makoto Komiyama

Nucleic Acids Res. Supple. 49 巻頁： 35-36 2005年

Design of Light-switchable Phage Promoter for Efficient Photo-regulation of Gene-expression

Minghe Liu, Hiroyuki Asanuma, Makoto Komiyama

Nucleic Acids Res. Supple. 49 巻頁： 283-284 2005年

Alternating hetero H-aggregation of different dyes by interstrand stacking from two DNA-dye conjugates

Hiromu Kashida, Hiroyuki Asanuma, Makoto Komiyama

Angew. Chem. Int. Ed. 43 巻 ( 47 ) 頁： 6522-6525 2004年

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

New hetero aggregates in which Methyl Reds and Naphthyl Reds are stacked alternately were successfully prepared by hybridization of two DNA-dye conjugates. When the Naphthyl Red conjugate was hybridized with Methyl Red conjugate, a new sharp absorption band (H-band) appeared at 480 nm that was different from the lmax of each dye conjugate in the single-stranded state. In addition to this new band in the UV-Vis spectrum, strong circular dichroism was also induced by interstrand hetero-stacking of these dyes. These results demonstrated that even different dyes as well as identical dyes could exhibit H-band.

Interstrand H aggregation of cationic dyes for narrowing the absorption spectra and stabilizing the duplex 査読有り

Hiromu Kashida, Hiroyuki Asanuma, Makoto Komiyama

Supramol. Chem. 16 巻 ( 6 ) 頁： 459-464 2004年

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

Interstrand H-aggregates of cationic dyes are prepared by hybridization of the two DNA-dye conjugates involving Naphthyl Red moiety and spacer alternately in the middle of the sequence. At pH 5.0 where Naphthyl Red is positively charged, single-stranded DNA-Naphthyl Red conjugate involving three dye groups and three spacer residues exhibited broad absorption spectrum having lmax at around 530 nm. But hybridization of two DNA-Naphthyl Red conjugates that are complementary provided rather different spectrum: much narrower absorption band appeared at 507 nm, which is 23 nm shorter than the single stranded conjugates. These spectroscopic behaviors indicate that dyes in the duplex are H-aggregated and excitons are strongly coupled in the aggregate. In addition to the appearance of narrow H-band, melting temperature dramatically increased by the H-aggregation of stacked cationic dyes compared with that of natural duplex without dye and spacer residues. Thus, positive charges on the stacked dyes did not interfere the duplex formation by the electrostatic repulsion, and moreover fairly promoted the hybridization.

Real time monitoring of the interaction of T7 RNA polymerase with azobenzene-tethered T7 promoter by biosensor

Minghe Liu, Hiroyuki Asanuma, Makoto Komiyama

Nucleic Acids Res. Supple. 4 4 巻頁： 221-222 2004年

Photoregulation of in vitro transcription/translation of GFP by tethering an azobenzene to T7 promoter

Jing Zhao, J. Zhou, Minghe Liu, Hiroyuki Asanuma, Makoto Komiyama

Nucleic Acids Res. Supple. 4 4 巻頁： 199-120 2004年

Photo-regulation of RNA Digestion by RNase H with Azobenzene-Tethered DNA 査読有り

Daijiro Matsunaga, Hiroyuki Asanuma, Makoto Komiyama

J. Am. Chem. Soc. 126 巻 ( 37 ) 頁： 11452-11453 2004年

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

RNA digestion by RNase H, which is responsible for the antisense effect, was efficiently photo-regulated by use of the duplex of azobenzene-tethered sense DNA and native antisense DNA. Under dark, RNA digestion was suppressed because antisense DNA was strongly hybridized with azobenzene-tethered sense DNA, and accordingly RNA was isolated. On UV light irradiation, antisense DNA was released from the azobenzene-tethered DNA due to the trans to cis isomerization and hybridized with RNA, which was digested by RNase H.

Efficient Separation of Hydrophobic Biomolecules by Molecularly Imprinted Cyclodextrins 査読有り

Hishiya, T.; Asanuma, H.; Komiyama, M.

J. Inclu. Phenom. Macrocyclic Chem. 50 巻頁： 51-55 2004年

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