Co-operative Research Study on Bacterial Surface Molecules and Bioresponse Modifying Activities in Host Animals.

根据初步的研究计划，我们研究了革兰氏阳性菌、革兰氏阴性菌和抗酸菌表面分子的结构-生物反应修饰活性。在革兰氏阴性菌中，研究了与外膜渗透性相关的孔蛋白亚基结构，Nakae等人证明了特别是假单胞菌和产碱菌属的性质。在耐酸细菌中，分枝菌酸和分枝菌酰糖脂（如索因子）的精细分子结构。由于已知这些特征糖脂具有独特的活性，因此在宿主动物中研究了免疫调节活性的基本结构。与这种抗酸细菌相关，Tamura分离出一种类似于革兰氏阴性LPS的新的两性菌组分。该组分的活性与革兰氏阴性内毒素相似，但毒性较低。由于目前尚缺乏有关革兰氏阳性细菌内毒素的资料，对其结构分析及对宿主动物的作用机制的研究将是今后的一个重要课题。最近，革兰氏阴性LPS的结构和活性的异质性。Takada等研究了从厌氧菌中分离的各种毒性较小的革兰氏阴性LPS。在革兰氏阳性菌中，磷壁酸（膜磷壁酸和壁磷壁酸）是特征成分之一。Kato等人报道了毒性较低的LTA的分离和表征，其可以产生无毒的TNF。LTA对宿主动物的活性有待进一步研究。同时还研究了产肠毒素E.大肠杆菌和副溶血性弧菌。Amako和Kawata等人利用电子显微镜对革兰氏阳性菌的精细结构进行了研究。我们希望上述项目在未来得到进一步的发展和进步，并得到科学研究资助计划的资助。

According to the initial plannings, we have investigated on the structure-bioresponse modifying activities of the surface molecules of gram-positive, gram-negative and acid-fast bacteria. In gram-negative bacteria, porin subunit structure which is related to the permeability of the outer membrane was investigated and the properties especially of Pseudomonas and Alcaligenes species were demonstrated by Nakae et al. In acid-fast bacteria, the fine molecular structure of mycolic acids and mycoloyl glycolipids such as cord factor. Since it has been known that these characteristic glycolipids possessed unique activities, the essential structure for immunomodifying activities was investigated in host animals. Related to this acid-fast bacteria, a new amphipatic fraction resembling to gram-negative LPS was isolated by Tamura. This fraction showed similar activities to the gram-negtive endotoxin, but less toxic. Since we have no information available about such gram-positive endotoxin, the structure analysis and mechanism of action on host animals would be greatly expected in future. Also recently, the heterogeneity of structure and activity of gram-negative LPS. Takada et al investigated on various less toxic gram-negative LPS isolated from anaerobic bacteria. In gram-positive bacteria, teichoic acids (membrane- and wall teichoic acids) are one of the characteristic components. Kato et al reported the isolation and characterization of less toxic LTA which can generate a non-toxic TNF. Activities of LTA on host animals should be more investigated in future. Exotoxin production and its secretion from the bacterial cells were also investigated especially with enterotoxigenic E. Coli and Vibrio parahaemolyticus. Fine structure analysis of gram-poam-positive bacteria was investigated by using electronmicroscopy by Amako and Kawata et al.We hope further development and progress of all the above projects in future and financial support from GRANT-IN-AID FOR SCIENTIFIC RESEARCH.