Crystal structure of a CAP-DNA complex: the DNA is bent by 90 degrees.
Schultz, S.C., Shields, G.C., Steitz, T.A.(1991) Science 253: 1001-1007
- PubMed: 1653449 
- PubMed Abstract: 
The 3 angstrom resolution crystal structure of the Escherichia coli catabolite gene activator protein (CAP) complexed with a 30-base pair DNA sequence shows that the DNA is bent by 90 degrees. This bend results almost entirely from two 40 degrees kin ...