Sedimentation Coefficients of Linear and Cyclic Wormlike Coils with Excluded-Volume Effects

Abstract

The sedimentation coefficient for the Kratky—Porod wormlike coil is calculated with the effects of excluded volume taken into account. The statistical length of native DNA is found to be 900 Å. The hydrodynamic diameter of the Watson—Crick helix is 26–27 Å. Sedimentation coefficients are calculated to decrease by about 13% on going from a cyclic native DNA to a linear molecule of the same molecular weight.