This research is directed toward understanding biological assembly processes at the molecular level, using assembly of the bacteriophage lambda virion as a model. The research focuses on assembly processes in which one protein influences or directs the assembly of another, and seeks to understand the detailed mechanisms behind such events. Specific problems being addressed include the structure and regulation of the E. coli GroE proteins, which are host proteins required for correct virus assembly, the nature and role of protein processing during virus assembly, and the mechanisms by which the tail tape measure protein determines tail length.