A Methodology for Constructing Taxonomy Trees and Perceptual Maps for Microorganism Classification

摘要

Because the lengths of DNA sequences for microorganisms are different, it is difficult to directly compare complete DNA sequences to investigate possible evolutional distances among microorganisms. In order to directly compare DNA sequences of microorganisms, a methodology comprised with quantization of DNA sequences, dimension reduction by Fourier transform, tree construction by hierarchical clustering analysis (HCA) and visualization of possible evolutional distances by multidimensional scaling (MDS) is proposed to help construct taxonomy trees and perceptual maps. Results analyzed from the complete DNA sequences of 4 Escherichia bacteria, 3 Pyrococcus archaea, 8 Bacillus bacteria and 4 Yersinia pestis bacteria indicate that the clustering consequences are corresponding to recent biological findings. It is suggested that the proposed methodology can be applied to microorganism classification.