Exploiting the structure of the Type 9 Secretion System protein translocon

向环境中分泌蛋白质是细菌生命的基本特征。这是致病菌引起疾病的机制。同样，将植物纤维分解成生物燃料的细菌必须分泌酶来消化纤维，因为纤维太大而无法被运送到细菌中。拟杆菌是一组重要的细菌，存在于动物和人类的消化道中，并且广泛存在于环境中。最近的研究表明，拟杆菌使用一种以前未发现的装置来输出蛋白质，称为9型分泌系统，简称T9SS。T9SS是牙齿病原体引起牙周病和引起鲑鱼和其他养殖鱼类的主要细菌性疾病所必需的。 我们最近分离了细菌细胞表面的孔，通过该孔T9SS分泌蛋白质，并使用电子显微镜确定其结构。我们将使用这些结构信息作为实验的基础，以了解T9SS孔如何运作。我们还将研究孔如何与T9SS的其他组分合作，以实现从细胞中输出蛋白质。 这项工作有可能帮助设计攻击致病拟杆菌的药物，并帮助我们了解如何利用其他拟杆菌从植物纤维中制造生物燃料。

Secretion of proteins into the environment is an fundamental feature of bacterial life. This is the mechanism by which pathogenic bacteria cause disease. Likewise, the bacteria that break down plant fibres into biofuels must secrete enzymes to digest the fibres because the fibres are too big to be transported into the bacterium. The Bacteroidetes are an important group of bacteria found in the digestive tracts of animals and humans, as well as being widespread in the environment. Recent research has shown that Bacteroidete bacteria use a previously-undiscovered apparatus to export proteins, called the type 9 secretion system, or T9SS for short. The T9SS is essential for dental pathogens to cause perditontal disease and to cause the main bacterial diseases of salmon and other farmed fish. We have recently isolated the pore in the bacterial cell surface through which the T9SS secretes proteins and have determined its structure using electron microscopy. We will use this structural information as a basis for experiments to understand how the T9SS pore operates. We will also investigate how the pore collaborates with other components of the T9SS to achieve protein export from the cell. This work has the potential to aid the design of drugs to attack pathogenic Bacteroidetes as well as to help us understand how to exploit other Bacteroidetes to make biofuels from plant fibres.