Study on the Membrane-damaging Action of Staphylococcal Alpha-toxin by use of Multilamellar Liposomes.

利用多层脂质体研究葡萄球菌α-毒素的膜损伤作用。

• 批准号: 01570230
• 负责人: TOMITA Toshio
• 金额: $ 1.34万
• 依托单位: The Institute of Medical Science, The University of Tokyo.
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1989
• 资助国家: 日本
• 起止时间: 1989 至 1990
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-01570230/
• 关键词: Staphylococcus aureus; alpha-toxin; membrane damage; liposome; transmembrane channel; membrane fluidity; monoclonal antibody; 毒素六量体形成

Staphylococcal alpha-toxin is a cytolytic 33K-Da polypeptide secreted by pathogenic Staphylococcus aureus. It binds to the membrane of target cells and assembles to hexamer, exhibiting transmembrane-channel activitiy. The toxin is considered to be a prototype for transmembrane-pore-forming proteins including streptolysin O, complement and perforin.By use of multilamellar liposome composed of Phosphatidyl-Choline (PC) as a model membrane, we studied influence of membrane fluidity on the assembly process of the toxin. Our results indicated that alpha-toxin assembled into hexameric form via a transient, nonhemolytic-monomer form, when PC membrane was fluidized either by the phase transition from gel to liquid crystalline state or by the inclusion of >30 mol % cholesterol in the PC membrane.To determine the domain of alpha-toxin which is involved in each step of the assembly process, we prepared monoclonal antibodies to the toxin. Monoclonal antibodies obtained from 14 different hybridoma strains were categorized to 3 groups according to their inhibitory action on binding and hemolytic activity of alpha-toxin. Analysis of the epitope which is recognized by each of the monoclonal antibodies is now in progress.

葡萄球菌α毒素是由致病性金黄色葡萄球菌分泌的溶细胞的33 K-Da多肽。它与靶细胞膜结合并组装成六聚体，表现出跨膜通道活性。以磷脂酰胆碱（PC）构成的多层脂质体为模型膜，研究了膜流动性对毒素组装过程的影响。我们的研究结果表明，当PC膜通过从凝胶到液晶态的相变或通过在PC膜中包含>30 mol %的胆固醇而流化时，α-毒素通过瞬时的非溶血单体形式组装成六聚体形式。从14个不同杂交瘤株获得的单克隆抗体根据其对α-毒素的结合和溶血活性的抑制作用分为3组。目前正在分析被每种单克隆抗体识别的表位。

项目成果

Tomita,T.,Watanabe,M.,Takahashi,T.,Kumai,K.,Tadakuma,T.,and Yasuda.T.: "Temperature-sensitive release of adriamycin,an amphiphilic antitumor agent,from dipalmitohlphophatidylcholine-cholesterol liposomes" Biochim.Biophys.Acta. 978. 185-190 (1989)

Tomita,T.、Watanabe,M.、Takahashi,T.、Kumai,K.、Tadakuma,T. 和 Yasuda.T.：“从二棕榈酰磷脂酰胆碱-胆固醇脂质体中温敏释放阿霉素（一种两亲性抗肿瘤剂）”

富田敏夫: "ブドウ球菌α毒素の膜障害機構について" 日本細菌学雑誌. 44. 67 (1989)

Toshio Tomita：“论葡萄球菌α毒素的膜损伤机制”日本细菌学杂志 44. 67 (1989)。

Yanagie, H., Tomita, T., Sekiguchi, M., and Nariuchi, H.: "Application of boron-10 entrapped in liposomes conjugated with anti-human CEA monoclonal antibody to boron-neutron capture therapy." Brit. J. Cancer Res.

Yanagie, H.、Tomita, T.、Sekiguchi, M. 和 Nariuchi, H.：“将硼 10 包埋在与抗人 CEA 单克隆抗体缀合的脂质体中在硼中子捕获疗法中的应用。”

Yanagie,H.,Tomita,T.,Sekiguchi,M.,Nariuchi,H.,and Kobayashi,H.: "Application of boronー10 entrapped in liposomes conjugated to antiーhuman CEA monoclonal antibody to boronーneutron capture therapy." Brit.J.Cancer Res.

Yanagie, H.、Tomita, T.、Sekiguchi, M.、Nariuchi, H. 和 Kobayashi, H.：“将硼 10 包埋在与抗人 CEA 单克隆抗体缀合的脂质体中在硼中子捕获疗法中的应用。 “英国癌症研究中心。

Nakata, M., Tomita, T., and Kanegasaki, S.: "Inhibitory effect of antibiotic cerulenin on the respiratory burst in phagocytes. I. Effects of cerulenin on active oxyaen-generation and lipid metabolism." J. Antibiotics. 42. 1171-1177 (1989)

Nakata, M.、Tomita, T. 和 Kanegasaki, S.：“抗生素浅蓝素对吞噬细胞呼吸爆发的抑制作用。I.浅蓝素对活性氧生成和脂质代谢的影响。”