Ethanol-induced structural transitions of DNA on mica

被引：86

作者：

Fang, Y

Spisz, TS

Hoh, JH

机构：

[1] Johns Hopkins Univ, Sch Med, Dept Physiol, Baltimore, MD 21205 USA

[2] Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA

来源：

NUCLEIC ACIDS RESEARCH | 1999年 / 27卷 / 08期

关键词：

D O I：

10.1093/nar/27.8.1943

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

The effect of ethanol on the structure of DNA confined to mica in the presence of Mg2+ was examined by varying the ethanol concentration and imaging the DNA by atomic force microscopy. Contour length measurements of the DNA show a transition from all-B-form at 0% ethanol to all-A-form at >25% ethanol. At intermediate ethanol concentrations, contour lengths suggest that individual molecules of air-dried DNA are trapped with mixed compositions of A-form and B-form. The relative composition depends on the ethanol concentration. Fitting the length distributions at intermediate ethanol concentrations to a simple binomial model results in an upper bound estimate for the A-form and B-form domains of similar to 54 bp in the individual molecules. In addition to length changes, the apparent persistence length of DNA decreases with increasing ethanol concentration. At high concentrations of ethanol (>20%), DNA formed several higher order structures, including flower shaped condensates and toroids.

引用

页码：1943 / 1949

页数：7

共 47 条

[1] THE HISTONE FOLD - A UBIQUITOUS ARCHITECTURAL MOTIF UTILIZED IN DNA COMPACTION AND PROTEIN DIMERIZATION [J].