Helical repeat and chirality effects on DNA gel electrophoretic mobility.

Helical repeat and chirality effects on DNA gel electrophoretic mobility.

We determined a value of 10.34 +/- 0.04 base pairs (bp) per turn for the helical repeat of bent DNA sequences of the form A6N4-A6N5 by estimating the sequence repeat required to produce a planar curve, as judged from the maximum in the electrophoretic mobility anomaly of multimers containing different sequence repeats (10.00, 10.33, 10.50, 10.67, and 11.00 bp per turn). This result provides the...

Sedimentation of macroscopic rigid knots and its relation to gel electrophoretic mobility of DNA knots

We address the general question of the extent to which the hydrodynamic behaviour of microscopic freely fluctuating objects can be reproduced by macrosopic rigid objects. In particular, we compare the sedimentation speeds of knotted DNA molecules undergoing gel electrophoresis to the sedimentation speeds of rigid stereolithographic models of ideal knots in both water and silicon oil. We find th...

Altered gel electrophoretic mobility of bleomycin-mediated release of nucleosomal DNA.

Nucleosomal DNA isolated from bleomycin-treated nuclei shows retarded electrophoretic mobility in neutral gels as compared with the sample isolated from micrococcal (or endogenous) nuclease-digested nuclei. The retardation in electrophoretic mobility is probably due to the presence of single-strand regions in the DNA duplex of bleomycin-treated samples as determined by single-strand-specific S1...

Helical repeat of DNA in solution.

The helical repeat of DNA in solution has been measured directly by analyzing the gel electrophoretic patterns of pairs of covalently closed DNAs with length differences between 1 and 58 base pairs, out of a total length of about 4350 base pairs per DNA molecule. The method is based on the observation that for a covalently closed DNA of a fixed size of n base pairs (n of the order of several th...

Effect of Fluorophores on Electrophoretic Mobility of Labeled DNA