PT - JOURNAL ARTICLE AU - GIOVANNI UGHETTO AU - MICHAEL J. WARING TI - Conformation of the Deoxyribonucleic Acid-Binding Peptide Antibiotic Echinomycin Based on Energy Calculations DP - 1977 May 01 TA - Molecular Pharmacology PG - 579--584 VI - 13 IP - 3 4099 - http://molpharm.aspetjournals.org/content/13/3/579.short 4100 - http://molpharm.aspetjournals.org/content/13/3/579.full SO - Mol Pharmacol1977 May 01; 13 AB - Potential energy calculations and geometrical requirements for ring closure limit the number of allowed conformations for the peptide ring of echinomycin to a very few. Refinement by a method of steepest descent beads to the selection of a minimum-energy conformation having substantial elements of twofold rotational symmetry, with the quinoxaline chromophores spaced approximately 10.2 A apart in a configuration which is compatible with simultaneous (bifunctional) intercalation into the DNA helix. ACKNOWLEDGMENTS We thank Drs. L. P. G. Wakelin, G. C. K. Roberts, and J. Feeney for critical discussion.