Pettersson B, Uhlén M, Johansson K E
Department of Biochemistry and Biotechnology, Royal Institute of Technology, Stockholm, Sweden.
Int J Syst Bacteriol. 1996 Oct;46(4):1093-8. doi: 10.1099/00207713-46-4-1093.
Almost complete (> 96%) 16S rRNA sequences from nine ruminant mycoplasmas have been determined by solid-phase DNA sequencing. Polymorphisms were found in four of the 16S rRNA sequences, which indicated the existence of two different rRNA operons. Seven polymorphisms were found in Mycoplasma agalatiae, three were found in Mycoplasma bovis, one was found in Mycoplasma alkalescens, and one was found in Mycoplasma bovirhinis. The sequence data were used for construction of phylogenetic trees. All but one of the ruminant mycoplasmas sequenced in this work clustered in the hominis group. A close relationship was found between M. agalactiae and M. bovis, with a 99% nucleotide similarity between their 16S rRNA sequences. They were also found to be members of the Mycoplasma lipophilum cluster of the hominis group. Furthermore, the 16S rRNA comparisons showed that Mycoplasma alkalescens and Mycoplasma canadense are closely related (> 98.5%), and these species were found to cluster in the Mycoplasma hominis cluster of the hominis group. Interestingly, M. bovirhinis grouped in a new phylogenetic cluster of the hominis group. The new cluster, which was supported by bootstrap percentage values, signature nucleotide analysis, and higher-order structural elements, was named the Mycoplasma synoviae cluster. Mycoplasma bovoculi, Mycoplasma conjunctivae, and Mycoplasma ovipneumoniae clustered in the Mycoplasma neurolyticum cluster of the hominis group. Mycoplasma alvi clustered with Mycoplasma pirum in the M. pneumoniae cluster of the pneumoniae group.
通过固相DNA测序已确定了9种反刍动物支原体几乎完整（> 96%）的16S rRNA序列。在16S rRNA序列中的4个序列中发现了多态性，这表明存在两种不同的rRNA操纵子。在无乳支原体中发现了7个多态性，在牛支原体中发现了3个，在碱性支原体中发现了1个，在牛鼻支原体中发现了1个。这些序列数据用于构建系统发育树。在这项研究中测序的反刍动物支原体中，除一种外，其他所有支原体都聚集在人型支原体组中。发现无乳支原体和牛支原体之间关系密切，它们的16S rRNA序列之间的核苷酸相似性为99%。它们还被发现是人型支原体组嗜脂支原体簇的成员。此外，16S rRNA比较表明，碱性支原体和加拿大支原体密切相关（> 98.5%），并且发现这些物种聚集在人型支原体组的人型支原体簇中。有趣的是，牛鼻支原体聚集在人型支原体组的一个新的系统发育簇中。这个新簇得到了自展百分比值、特征核苷酸分析和高级结构元件的支持，被命名为滑膜支原体簇。牛眼支原体、结膜支原体和绵羊肺炎支原体聚集在人型支原体组的溶神经支原体簇中。盲肠支原体与梨支原体一起聚集在肺炎支原体组的肺炎支原体簇中。
