Matsuzawa Y, Yoshikawa K
Graduate School of Human Informatics, Nagoya University, Japan.
Nucleic Acids Symp Ser. 1993(29):147-8.
We have studied the conformational change of T4DNA molecules in aqueous polyethylene glycol (PEG) solution by use of fluorescence microscopy. It was found that the DNA molecules exhibit abrupt transition from elongated coil into shrunken globule conformations depending on the concentration of PEG6000, a polymer with 186 monomer units. Interestingly, PEG20M, with 454 monomer units, shows two different types of transition; coil-globule transition around 0.1 M and globule-coil transition above 1 M. Such transitions are expected to be related to the regulation of gene expression and replication in living cells.
我们通过荧光显微镜研究了T4DNA分子在聚乙二醇（PEG）水溶液中的构象变化。发现DNA分子会根据PEG6000（一种具有186个单体单元的聚合物）的浓度，从伸长的线圈状突然转变为收缩的球状构象。有趣的是，具有454个单体单元的PEG20M表现出两种不同类型的转变；在0.1 M左右发生线圈-球状转变，在1 M以上发生球状-线圈转变。这种转变预计与活细胞中基因表达和复制的调控有关。
