A simple model of the conformational transition between the right handed B double helix and the left handed Z double helix of DNA is proposed. This is a mechanistic model in which the dependence of the energy on twist is represented by two terms, one which depends upon the shape of the potential energy. This second term reflects the resistance of the DNA to deformations. With such a simple model we have studied cases of homogeneous chains with symmetric potential energies, as well as those within homogeneities and asymmetries in which one conformation is preferred over the other, for a portion of the chain. The method yields the location of the B-Z conformational boundaries for different conditions. Comparisons have been made with experiments in which G-C regions have been inserted in circular plasmid DNA. Additional methods have been developed to deal explicitly with the conformational statistics through this transition.

Agency
National Institute of Health (NIH)
Institute
Division of Cancer Biology And Diagnosis (NCI)
Type
Intramural Research (Z01)
Project #
1Z01CB008371-02
Application #
4691845
Study Section
Project Start
Project End
Budget Start
Budget End
Support Year
2
Fiscal Year
1985
Total Cost
Indirect Cost
Name
Cancer Biology and Diagnosis
Department
Type
DUNS #
City
State
Country
United States
Zip Code