DNA Structure in Sheared and Unsheared Chromatin

Abstract

Shearing chromatin, by either sonication or vortex homogenization, introduces significant structural artifacts. These may be detected by the anomalously large increase in the number of ethidium bromide binding sites and the large alteration of the circular dichroism spectra of chromatin. Structural alterations are also suggested by the disappearance of differential light scattering after shearing.