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.
