DIRECT OBSERVATION OF TUBE-LIKE MOTION OF A SINGLE POLYMER-CHAIN

被引：431

作者：

PERKINS, TT ^{[1
]}

SMITH, DE ^{[1
]}

CHU, S ^{[1
]}

机构：

[1] STANFORD UNIV, DEPT PHYS, STANFORD, CA 94305 USA

来源：

SCIENCE | 1994年 / 264卷 / 5160期

关键词：

D O I：

10.1126/science.8171335

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Tube-like motion of a single, fluorescently labeled molecule of DNA in an entangled solution of unlabeled lambda-phage DNA molecules was observed by fluorescence microscopy. One end of a 16- to 100-micrometer-long DNA was attached to a 1-micrometer bead and moved with optical tweezers. The molecule was stretched into various conformations having bends, kinks, and loops. As the polymer relaxed, it closely followed a path defined by its initial contour. The relaxation time of the disturbance caused by the bead was roughly 1 second, whereas tube-like motion in small loops persisted for longer than 2 minutes. Tube deformation, constraint release, and excess chain segment diffusion were also observed. These observations provide direct evidence for several key assumptions in the reptation model developed by de Gennes, Edwards, and Doi.

引用

页码：819 / 822

页数：4

共 27 条

[1] OBSERVATION OF A SINGLE-BEAM GRADIENT FORCE OPTICAL TRAP FOR DIELECTRIC PARTICLES [J].