The objective of this project is to determine the three dimensional structure of the complex between gene repressors and their specific binding site on the DNA. The primary method to be used will be an extensive application of two dimensional nuclear magnetic resonances methods. The systems that are to be investigated are: 1) the lac repressor and lac operator DNA from the lactose operon of E. coli 2) the lambda phage cro gene product and its operators. A variety of genetic manipulations will be used to both obtain adequate amounts of the macromolecules to be studied as well as to generate variants. The use of genetically produced variants will be crucial to understanding the important molecular features of these protein-nucleic acid complexes. The lactose operon repressor and the lambda cro gene product interact with specific DNA sequences and thus serve as prototype systems for the study of gene regulation and chromosome structure.
