The Role and Mechanism of Gene 12 Product in the T4 Phage Infection Process

本次美苏合作研究项目的目的是阐明T4噬菌体短基板纤维P12的结构和功能。P12是噬菌体T4不可逆地附着到宿主大肠杆菌上的细胞器。P12将在分离和噬菌体颗粒上作为细胞器进行研究。将开发一种检测方法，对gp12单体和P12三聚体单元进行纯化，并进行生理、生物能量、结构和遗传的综合研究。这个美苏合作研究项目的提案将结合三位研究者的技术优势：塔夫茨大学的E. Goldberg，美国科学家，是噬菌体宿主识别、附着和注射的生理学和遗传学专家。来自苏联的两名调查人员将参加。莫斯科伊万诺夫斯基病毒学研究所（Ivanovsky Institute of Virology）的梅扬日诺夫（V. Mesyanzhinov）专长是生物化学，他对gp12及其周围的基因进行了亚克隆和测序，并开发了一种纯化gp12单体和P12三聚体的方法。维尔纽斯大学（Vilnius University）的生物能量学专家L. Grinius最近研究了噬菌体附着过程中宿主细菌的去极化。他的实验室开发了一种特殊的电极膜电位测量方法，可以实时准确地测量变化。这项合作将提供必要的方法组合来表征P12的组成、组装、生理作用和作用机制。这项美国/苏联合作项目将有助于更好地了解一种纤维蛋白的结构和作用机制，这种纤维蛋白负责将细菌病毒“T4”附着在其宿主细菌大肠杆菌上。在这种蛋白质附着到细菌上的过程中，蛋白质改变了它的结构，并促进了细菌膜通透性的变化。分离出的蛋白质也有杀死细菌的能力。该项目的结果将有助于了解一些最基本的生物学问题：分子水平上的识别，控制膜通透性的通道的形成和结构机制，以及病毒杀死细菌的机制。

The objective of this US/USSR collaborative research project is to clarify the structure and function of the short baseplate fiber, P12, of T4 bacteriophage. P12 is the organelle by which phage T4 irreversibly attaches to its host, E. coli. P12 will be studied both in isolation and as an organelle on the phage particle. An assay will be developed and gp12 monomer as well as the P12 trimer unit will be purified, and a combination of physiological, bioenergetic, structural and genetic studies will be undertaken. This proposal for a US/USSR collaborative research project will combine the technical strengths of three investigators: E. Goldberg, of Tufts University, the US scientist, is an expert in the physiology and genetics of bacterophage host recognition, attachment, and injection. Two investigators from the USSR will participate. V. Mesyanzhinov, of the Ivanovsky Institute of Virology, Moscow, whose expertise is biochemistry has subcloned and sequenced gp12 and the genes surrounding it, and has developed a method for purification of the gp12 monomer and the P12 trimer. L. Grinius, of Vilnius University, an expert in bioenergetics, has recently worked on the depolarizaton of the host bacterium during phage attachment. His laboratory has developed a specific electrode form membrane potential measurements which can accurately measure changes in real time. This collaboration will provide the combination of approaches necessary to characterize the composition, assembly, physiological role and mechanism of action of P12. This US/USSR collaborative project should lead to a better understanding of the structure and mechanism(s) of action of a fibrous protein responsible for the attachment of the bacterial virus, "T4", to its host bacterium, E. coli. During attachment of this protein to the bacterium the protein changes its configuration and promotes changes in the permeability of the bacterial membrane. The isolated protein also has the ability to kill the bacteria. The results of this project will contribute to basic knowledge of some of the most fundamental problems of biology: recognition at the molecular level, the mechanism of formation and structure of channels controlling the permeability of membranes, and the mechanism of bacterial killing by a virus.