分子馬達（molecular motors）其工作環境是在奈米尺度下，利用ATP水解及水解產物的釋放，將此化學能轉換成機械功，進而產生機械運動，是目前主要的議題。例如Dynein蛋白質酵素分子，在運動時會產生鍵結在微管上與脫離微管之連續動作。本文使用兩構形狀態（two-states）之運動模型來模擬其運動情況。在此模型中，採用Fokker-Planck equation為運動方程式，並運用能量觀點可適切地分析受到位能梯度之影響。

本文使用一套建構在破壞精細平衡（detailed balance）上的數值演算法，來探討分子馬達化學轉換的過程。此演算法是用連續馬可夫過程（continuous Markov process）描述其跳躍過程（jump process）與跳躍率（jump rate），來解此系統運動模式。

運用上述方法，並採用MATLAB7.0軟體，分析在無外力作用、有外力作用與ATP濃度變化對其速度、有效擴散係數與隨機性之影響。得到之結果，對分子馬達化學能轉換成機械功之理論分析有所幫助。

How molecular motors that function at nano scale convert chemical energy from adenosine triphosphate(ATP) into mechanical force and motion is the one of the main themes of modern biology. Dynein, a protein enzyme, alternates between binding and unbinding with microtubule in motion. This paper used two-states model to investigate the movement behaviors of molecular motor. The Fokker-Planck equation was used to analyze how potential influens molecular motor.

We use a numerical algorithm that presented by Wang, et al. to study of biomolecular transport processes. In the algorithm a continuous Markov process is discretized as a jump process and the jump rates are derived from local solutions of the continuous system.

We used the algorithm solved by Matlab 7.0 to calculate the mean velocities, the effective diffusion coefficient and the randomness parameter of the molecular that subjected to external load or not.Analytical results of this study are discussed to provide further insight into the chemomechanical theory of molecular motor.

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