Insights into the Discrepancy between Single Molecule Experiments *

Qian Zhou,Min Zhang,Yang-Tao Fan,Yu-Kang Wang,Lin Bao,Guang-Ju Zhao,Hu Chen,Yan-Hui Liu

Fig. 2 (Color online) Fork generation at junction of dsDNA and ssDNA under conditions without kink generation in dsDNA. Loop lengths of the sensor in Figs. 2(a)-2(d) are 37 bp, 57 bp, 81 bp, and 101 bp, respectively, in which the loop is complemented by ssDNA with different lengths to form dsDNA; generation frequency of forks pertains to contour lengths of dsDNA in sensor proportionally. A critical contour length of dsDNA exists in every sensor and their values are 20 bp, 33 bp, 51 bp, and 63 bp, respectively. Only when the contour length of dsDNA in sensor becomes larger than the critical length does the fork structure begins to be generated.