分类: 物理学 >> 交叉学科物理及相关领域的科学与技术 提交时间: 2016-05-08
摘要: Single-molecule experiments revealed that the replication rate of T7 DNA polymerase has a peak value at tension of about 5.5 pN. However, the mechanism leading to this peak has only been partially investigated. Here, we present a two-state model to investigate the effect of mechanical tension on DNApolymerase activity. The model consists of polymerase and exonuclease. The polymerase's kinetic pathway has been simplified into Michaelis-Menten formwith two steps. One is the conformational change from "open" to "close". The other is the base-stacking. The results are in good agreement with experimental observations. We also predict that the tension on template is beneficial to the fidelity of DNA replication.
分类: 物理学 >> 交叉学科物理及相关领域的科学与技术 提交时间: 2016-05-08
摘要: Within the framework of a two-state ratchet model, cooperative effects of collective molecular motors on the kinetics of adenosine triphosphate (ATP) hydrolysis have been studied in detail. We calculate the dependence of the rate of ATP consumption on the applied load. Features different from a single molecular motor have been found. We analyze two typical oscillations of collective molecular motors. The relations between the ATP concentration and oscillatory characteristics, such as frequency, amplitude, and the duty ratio, have been discussed.