Pettersson B, Kodjo A, Ronaghi M, Uhlén M, Tønjum T
Department of Biochemistry and Biotechnology, Royal Institute of Technology, Stockholm, Sweden.
Int J Syst Bacteriol. 1998 Jan;48 Pt 1:75-89. doi: 10.1099/00207713-48-1-75.
Thirty-three strains previously classified into 11 species in the bacterial family Moraxellaceae were subjected to phylogenetic analysis based on 16S rRNA sequences. The family Moraxellaceae formed a distinct clade consisting of four phylogenetic groups as judged from branch lengths, bootstrap values and signature nucleotides. Group I contained the classical moraxellae and strains of the coccal moraxellae, previously known as Branhamella, with 16S rRNA similarity of > or = 95%. A further division of group I into five tentative clusters is discussed. Group II consisted of two strains representing Moraxella atlantae and Moraxella osloensis. These strains were only distantly related to each other (93.4%) and also to the other members of the Moraxellaceae (< or = 93%). Therefore, reasons for reclassification of these species into separate and new genera are discussed. Group III harboured strains of the genus Psychrobacter and strain 752/52 of [Moraxella] phenylpyruvica. This strain of [M.] phenylpyruvica formed an early branch from the group III line of descent. Interestingly, a distant relationship was found between Psychrobacter phenylpyruvicus strain ATCC 23333T (formerly classified as [M.] phenylpyruvica) and [M.] phenylpyruvica strain 752/52, exhibiting less than 96% nucleotide similarity between their 16S rRNA sequences. The establishment of a new genus for [M.] phenylpyruvica strain 752/52 is therefore suggested. Group IV contained only two strains of the genus Acinetobacter. Strategies for the development of diagnostic probes and distinctive sequences for 16S rRNA-based species-specific assays within group I are suggested. Although these findings add to the classificatory placements within the Moraxellaceae, analysis of a more comprehensive selection of strains is still needed to obtain a complete classification system within this family.
对先前分类为莫拉克斯氏菌科11个种的33株菌株基于16S rRNA序列进行了系统发育分析。根据分支长度、自展值和特征核苷酸判断，莫拉克斯氏菌科形成了一个由四个系统发育组组成的独特进化枝。第一组包含经典莫拉克斯氏菌和球菌性莫拉克斯氏菌菌株（以前称为布兰汉菌属），其16S rRNA相似性≥95%。讨论了将第一组进一步划分为五个暂定簇。第二组由代表大西洋莫拉克斯氏菌和奥斯陆莫拉克斯氏菌的两株菌株组成。这些菌株彼此之间亲缘关系较远（93.4%），与莫拉克斯氏菌科的其他成员也亲缘关系较远（≤93%）。因此，讨论了将这些种重新分类到单独的新属中的原因。第三组包含嗜冷杆菌属的菌株和苯丙酮酸[莫拉克斯氏菌]的752/52菌株。苯丙酮酸[莫拉克斯氏菌]的这一菌株从第三组的进化谱系中形成一个早期分支。有趣的是，在苯丙酮酸嗜冷杆菌ATCC 23333T菌株（以前分类为苯丙酮酸[莫拉克斯氏菌]）和苯丙酮酸[莫拉克斯氏菌]752/52菌株之间发现了较远的亲缘关系，它们的16S rRNA序列之间的核苷酸相似性小于96%。因此建议为苯丙酮酸[莫拉克斯氏菌]752/52菌株建立一个新属。第四组仅包含两株不动杆菌属的菌株。提出了在第一组内开发基于16S rRNA的种特异性检测诊断探针和独特序列的策略。尽管这些发现增加了莫拉克斯氏菌科内的分类定位，但仍需要分析更全面的菌株选择以获得该科内完整的分类系统。
