Chain length of closed circle DNA is equal. The same closed circle DNA＇s position corresponds to different recognition sequence, and the same recognition sequence corresponds to different foreign DNA segment, so closed circle DNA computing model is generalized. For change positive-weighted Hamilton circuit problem, closed circle DNA algorithm is put forward. First, three groups of DNA encoding are encoded for all arcs, and deck groups are designed for all vertices. All possible solutions are composed. Then, the feasible solutions are filtered out by using group detect experiment, and the optimization solutions are obtained by using group insert experiment and electrophoresis experiment. Finally, all optimization solutions are found by using detect experiment. Complexity of algorithm is concluded and validity of DNA algorithm is explained by an example. Three dominances of the closed circle DNA algorithm are analyzed, and characteristics and dominances of group delete experiment are discussed.
Inspired by the potential computational capability of 3-Dimensional (3D) DNA structure,this paper presents a graph structure constructed by k-armed (k = 3or 4) branched junction DNA molecules to explore the possibility of solving some intractable problems. In the proposed procedure,vertex building blocks consisting of 3,4-armed branched junction molecules are selectively used to form different graph structures. After separating these graph structures by gel electrophoresis,the connec-tivity of this graph can be determined. Furthermore,the amount of potential solutions can be reduced by a theorem of graph theory.
A special DNA computer was designed to solve the vertex coloring problem. The main body of this kind of DNA computer was polyacrylamide gel electrophoresis which could be classified into three parts: melting region, unsatisfied solution region and solution region. This polyacrylamide gel was con- nected with a controllable temperature device, and the relevant temperature was Tm1, Tm2 and Tm3, res- pectively. Furthermore, with emphasis on the encod- ing way, we succeeded in performing the experiment of a graph with 5 vertices. In this paper we introduce the basic structure, the principle and the method of forming the library DNA sequences.
