A Statistical Mechanical Model for Predicting B-DNA Curvature and Flexibility

✍ Scribed by LU TSAI; LIAOFU LUO

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 281 KB
• Volume: 207
• Category: Article
• ISSN: 0022-5193
• DOI: 10.1006/jtbi.2000.2162

✦ Synopsis

A statistical mechanical model taking into account the symmetric twisting, tilting, sliding #uctuations and asymmetric rolling #uctuations has been proposed to predict the macroscopic curvature and #exibility of B-DNA. Based on the statistical data of structural parameters of double helix in nucleic acid database and the related theoretical analysis, the equilibrium angular parameters ( , and ) describing the orientation of successive base-pair planes, the translation parameters (D W ) along the long axis of neighboring base-pair step and the corresponding force constants are arranged for ten dimers appropriately. Under the assumption of independent angular parameters, independent base-pair steps and a simple energy function, we can calculate the macroscopic curvature and the #exibility of DNA sequences through the transformation matrix 1R2 and the Boltzmann ensemble average. The predictions on curvature and #exibility of DNA have been compared with the corresponding experimental data. The agreement is remarkably good. It is demonstrated that the lowering of the temperature does increase the DNA curvature.