著者

荒木 敏一 伊藤 道治 池田 温 池田 誠 稻葉 一郎 岩見 宏 上田 早苗 植松 正 梅原 郁 江幡 眞一郎 小田 壽典 小谷 仲男 小野 信爾 愛宕 松男 織田 武雄 大島 利一 大谷 敏夫 狩野 直禎 勝藤 猛 河内 良弘 河地 重蔵 神戸 輝夫 衣川 強 楠山 修作 小玉 新次郎 近藤 治 佐伯 富 佐竹 靖彦 佐藤 圭四郎 佐藤 長 佐藤 陸雄 重松 伸司 島居 一康 島田 虔次 菅野 正 杉村 邦彦 田中 整治 田村 實造 谷 光隆 谷川 道雄 谷口 規矩雄 竺沙 雅章 寺田 隆信 寺廣 映雄 礪波 護 中谷 英雄 永田 英正 西里 喜行 波多野 善大 萩原 淳平 日比野 丈夫 藤枝 晃 藤本 勝次 藤善 眞澄 藤原 利一郎 堀田 伊八郎 間野 英二 宮川 尚志 村上 嘉實 森 正夫 森本 公誠 柳田 節子 横山 裕男 吉川 忠夫 若松 寛

出版者

東洋史研究會

雑誌

東洋史研究 (ISSN:03869059)

巻号頁・発行日

vol.54, no.4, pp.5-74, 1996-03-31

著者

大谷敏夫著

出版者

同朋舎出版

巻号頁・発行日

1995

著者

佐川 久美子 佐々木 徹 大谷 敏夫 兵頭 昭夫 石田 直文 西川 昌子 梅野 幸彦

出版者

公益社団法人 日本化学療法学会

雑誌

CHEMOTHERAPY (ISSN:00093165)

巻号頁・発行日

vol.42, no.Supplement2, pp.263-276, 1994-10-24 (Released:2011-08-04)

参考文献数

13

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Tazobactam/piperacillin (TAZ/PIPC; tazobactam: piperacillin=1: 4) の体内動態を解明するために, bioassay法およびHPLC法により, tazobactam (TAZ) とpiperacillin (PIPC) の分別定量法を検討した。Bioassay法において, TAZはそれ自身の抗菌力が弱いため, 培地中にcefoperazone (CPZ) を150μg/ml添加し, CPZ高度耐性でβ-lactamaseを産生するEscherichia coli 603を検定菌とする方法により, 定量が可能であった。PIPCはMicrococcus luteus ATCC 9341を検定菌とするbioassay法により, TAZの影響をほとんど受けずに測定可能であった。HPLC法においては, Inertsil ODS-2カラムを用いることによって, TAZ, PIPCおよびPIPCの活性代謝物desethyl-PIPCを同時に分別定量することが可能であった。また, TAZの非活性代謝物M-1についてはDevelosil ODS-5カラムを用いることにより定量可能であった。Bioassay法とHPLC法の相関関係について, ヒトの血漿および尿を用いた添加回収試験で検討した結果, 両者間には良好な相関関係が認められた。

著者

大谷 敏夫

出版者

大阪府立大学

巻号頁・発行日

1990

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博士論文

著者

吉田 健一郎 東 龍太郎 佐伯 真由子 南 慶典 大谷 敏夫

出版者

天然有機化合物討論会実行委員会

雑誌

天然有機化合物討論会講演要旨集 35 (ISSN:24331856)

巻号頁・発行日

pp.250-257, 1993-09-10 (Released:2017-08-18)

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Antibiotic C-1027, a novel antitumor chromoprotein isolated from the broth filtrate of Streptomyces globisporus C-1027, shows extremely potent cytotoxicity against KB carcinoma cells (IC_<50> 0.1ng/ml) in vitro and antitumor activity toward tumor-bearing mice in vivo. These activities are correlated with the ability of the antibiotic to cause DNA double-strand scission. The antibiotic consists of an apoprotein and a labile chromophore (C-1027-Chr) that is responsible for the biological activity of C-1027. The chromophore is readily separated from its apo-protein by extraction, but the exceeding instability in the protein-free state hampered the structure elucidation. The similar situation has been also observed in the other chromoprotein antibiotics of this family such as neocarzinostatin (NCS), macromomycin, auromomycin (AUR), actinoxanthin and kedarcidin. Among them, NCS is the only one whose chromophore structure has been elucidated, and very recently, the structural novelty of kedarcidin chromophore has been disclosed by the Bristol-Myers Squibb group. We have characterized an inactive but more stable reaction product (2) of C-1027-Chr, which was prepared by treatment of C-1027-Chr in ethanol. It possesses a macrocyclic structure together with oxazolinate and aminosugar moieties as side chains. Its benzodihydropentalene core structure suggested to us the presence of an enediyne in the native C-1027-Chr. We disclose herein the novel structure of C-1027-Chr (1) and the cycloaromatization mechanism leading to product (2), which would explain its extreme potency in terms of cytotoxicity and ability to cause DNA double-strand scission.

著者

石塚 みどり 田中 俊之 福田 純子 平間 正博 大谷 敏夫

出版者

天然有機化合物討論会実行委員会

雑誌

天然有機化合物討論会講演要旨集

巻号頁・発行日

vol.42, pp.331-336, 2000

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C-1027 is a potent antitumor antibiotic, in which a nonprotein chromophore is tightly and specifically bound to an apoprotein. The chromophore, which has an endiyne structure and is responsible for DNA cleavage, is very labile when isolated, but greatly stabilized through binding to the apoprotein. Their binding structure and stabilizing interactions are very interesting problems in terms of molecular recognition and protein transport. The 3D structure of C-1027 apoprotein was determined by the X-PLOR calculation using 1539 experimental restrains derived from NMR spectroscopy. The apoprotein has three antiparallel β-sheets, and the hydrophobic pocket is formed by four-stranded β-sheet (DCHI) and two loops (residues 75-79, 97-100)(Fig.3). The overall shape of the apoprotein is quite similar to those of neocarzinostatin (NCS) and actinoxanthin (AXN). The binding structure of C-1027 complex was calculated based on 1539 NMR-derived constraints which include 38 intermolecular restraints between the aromatized chromophore and the apoprotein. The aromatized chromophore is bound to the hydrophobic pocket of the apoprotein. The benzodihydropentalene core locates in the center of the pocket with its molecular plane almost perpendicular to the bottom of the pocket. The β-tyrosine unit locates on the left side of the core, and both benzoxazine and aminosugar moieties on the right side (Fig.4). The hydrophobic interaction is most likely the major binding interaction between the apoprotein and the aromatized chromophore. Moreover, the 18-amino group of the chromophore locates in the proximity of either the carboxylate of Asp101 or the imidazole ring of His104, which indicates there could be a salt-bridge or a hydrogen bond type interaction between the aromatized chromophore and these side chains. To confirm the predicted binding interactions, we made several mutant apoproteins whose specific amino acid residue is replaced with the amino acid of different type and examined their binding abilities for the aromatized chromophore by NMR. The results obtained will be discussed.

著者

臼杵 豊展 井上 将行 平間 正博 田中 俊之 細井 文仁 大家 真治 大谷 敏夫

出版者

天然有機化合物討論会実行委員会

雑誌

天然有機化合物討論会講演要旨集

巻号頁・発行日

vol.45, pp.257-262, 2003

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The antitumor antibiotic C-1027 is a 1:1 complex of a highly labile enediyne chromophore (1) and a carrier apoprotein. C-1027 exhibited the potent cytotoxicity toward various cancer cells. The p-benzyne biradical (2), which is in equilibrium with 1, abstracts hydrogens from DNA to exert its biological activity. The apoprotein functions as both the stabilizer and the drug delivery system of 1. Recently, we found that the biradical 2 slowly abstracts α-proton of Gly96 of the apoprotein, which caused the oxidative cleavage of the peptides and led to a self-degradation of C-1027. To create a more stable analog of antibiotic C-1027, we designed a Gly96-deuterated (D-Gly) apoprotein. The D-Gly apoprotein was expressed in Escherichia coli in the presence of glycine-d_5. The unstable chromophore 1, isolated from natural C-1027, was then incorporated into the D-Gly apoprotein using HPLC techniques to obtain the D-Gly C-1027. Stability tests revealed that the D-Gly C-1027 was 1.8 and 4.9 times as stable as the natural one under solid and solution states, respectively. Cytotoxicity test also reflected the stability of D-Gly C-1027. Thus, we achieved the creation of supranatural products by rational design utilizing kinetic isotope effect. The presented work demonstrated the novel design principle to create the supra-natural products by integrating the data of physicochemical property of the small molecule and the atomic-level 3D-structure of the protein, which will be applicable to other biologically important natural products and proteins.

著者

吉田 健一郎 東 龍太郎 佐伯 真由子 南 慶典 大谷 敏夫

出版者

天然有機化合物討論会実行委員会

雑誌

天然有機化合物討論会講演要旨集

巻号頁・発行日

vol.35, pp.250-257, 1993

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Antibiotic C-1027, a novel antitumor chromoprotein isolated from the broth filtrate of Streptomyces globisporus C-1027, shows extremely potent cytotoxicity against KB carcinoma cells (IC_<50> 0.1ng/ml) in vitro and antitumor activity toward tumor-bearing mice in vivo. These activities are correlated with the ability of the antibiotic to cause DNA double-strand scission. The antibiotic consists of an apoprotein and a labile chromophore (C-1027-Chr) that is responsible for the biological activity of C-1027. The chromophore is readily separated from its apo-protein by extraction, but the exceeding instability in the protein-free state hampered the structure elucidation. The similar situation has been also observed in the other chromoprotein antibiotics of this family such as neocarzinostatin (NCS), macromomycin, auromomycin (AUR), actinoxanthin and kedarcidin. Among them, NCS is the only one whose chromophore structure has been elucidated, and very recently, the structural novelty of kedarcidin chromophore has been disclosed by the Bristol-Myers Squibb group. We have characterized an inactive but more stable reaction product (2) of C-1027-Chr, which was prepared by treatment of C-1027-Chr in ethanol. It possesses a macrocyclic structure together with oxazolinate and aminosugar moieties as side chains. Its benzodihydropentalene core structure suggested to us the presence of an enediyne in the native C-1027-Chr. We disclose herein the novel structure of C-1027-Chr (1) and the cycloaromatization mechanism leading to product (2), which would explain its extreme potency in terms of cytotoxicity and ability to cause DNA double-strand scission.