title: Phylogeny of the family Moraxellaceae by 16S rDNA sequence analysis, with special emphasis on differentiation of Moraxella species.
abstract: 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.
authors.affiliation: Department of Biochemistry and Biotechnology, Royal Institute of Technology, Stockholm, Sweden.
authors.forename: B
authors.initials: B
authors.lastname: Pettersson
authors.forename: A
authors.initials: A
authors.lastname: Kodjo
authors.forename: M
authors.initials: M
authors.lastname: Ronaghi
authors.forename: M
authors.initials: M
authors.lastname: Uhlén
authors.forename: T
authors.initials: T
authors.lastname: Tønjum
mesh_terms: D017931:DNA Primers; D004269:DNA, Bacterial / Q000032:analysis; D008969:Molecular Sequence Data; D016955:Moraxella bovis / Q000145:classification* / Q000235:genetics*; D001936:Moraxella catarrhalis / Q000737:chemistry* / Q000235:genetics*; D009841:Oligonucleotides; D010802:Phylogeny; D012329:RNA, Bacterial / Q000032:analysis; D012336:RNA, Ribosomal, 16S / Q000032:analysis*; D013045:Species Specificity
chemical_list: D017931:DNA Primers; D004269:DNA, Bacterial; D009841:Oligonucleotides; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S