鼻疽假单胞菌与类鼻疽假单胞菌的基因分类

目的：对鼻疽假单胞菌和类鼻疽假单胞菌进行基因分类研究。方法：应用16SrDNA扩增，基因测序及微孔板定量杂交技术，从基因水平对具有不同生物学特性的鼻疽假单胞菌和类鼻疽假单胞菌两个标准菌株进行同源性分析。结果：尽管两种细菌在生物学特性上有着明显的差异。但其16SrDNA序列相似度达99%以上，且染色体DNA定量杂交也显示大于70%的同源性。结论：鼻疽假单胞菌和类鼻疽假单胞菌的系统发育关系十分密切，应归属于同一种，是否妥当仍待进一步考证。

Taxonomic Studies on Pseudomonas Mallei and Pseudomonas Pseudomallei

Objective: To study the taxonomic relationship between Pseudomonas mellei and Pseudomonas pseudomallei. Methods: The techniques of 16S rDNA sequence analysis and DNA/DNA hybridization in microdilution wells were used to determine genetic relatedness between Pseudomonas mellei and Pseudomonas pseudomallei. The CLUSTAL-W software was used to align the sequences, and the phylogenetic distance was calculated by using the neighbor-joining(NJ) method. The phylogenetic tree was drawn by using Tree View software. Results: The 16S rDNA sequence of Pseudomonas mallei was more than 99% related to the species of Pseudomonas pseudomallei. There was a higher value (>70%) of quantitative DNA/DNA hybridization between the two species. Conclusions: It indicated that the specie Pseudomonas mallei and specie Pseudomonas pseudomallei are phylogenetically closely related. By these genetic evidences, we discuss taxonomic problems of the genus Pseudomonas.