Woolley K J, Athalye M
Biochem Biophys Res Commun. 1986 Nov 14;140(3):808-13. doi: 10.1016/0006-291x(86)90705-9.
Principal Coordinate analysis (PCO) was applied to the comparison of protein sequences. A similarity matrix was derived from a dataset containing 21 c-type cytochrome sequences and this was analysed using PCO to produce a plot of the first three principal axes. The relationships indicated from this plot are considered in conjunction with those derived by cluster analysis using the UPGMA method, and the advantages offered by a nonhierarchical method of sequence comparison discussed.
主坐标分析（PCO）被应用于蛋白质序列的比较。从一个包含21个c型细胞色素序列的数据集得出一个相似性矩阵，并使用PCO对其进行分析，以生成前三个主轴的图。结合使用UPGMA方法通过聚类分析得出的关系来考虑此图所示的关系，并讨论序列比较的非层次方法所具有的优势。
