Showing papers by "Michael Goodfellow published in 1995"

A phylogenetic analysis of the genus Nocardia with 16S rRNA gene sequences

Abstract: Partial sequences of the 16S rRNA genes of the type strains of nine species of the genus Nocardia were determined following the isolation and cloning of the amplified genes. These sequences were aligned with the sequences of representatives of the genera Corynebacterium, Gordona, Mycobacterium, Rhodococcus, and Tsukamurella, and phylogenetic trees were inferred by using the Fitch-Margoliash and neighbor-joining methods. The genus Nocardia formed a distinct clade that was most closely associated with the genus Rhodococcus. The average level of sequence similarity found among the type strains of the Nocardia species was 97.2 ± 0.7%. Two sublines were recognized within the Nocardia clade; one encompassed Nocardia asteroides and related species, and the other encompassed Nocardia otitidiscaviarum and allied taxa. Separation of the two sublines is based on differences in helix 37–1. The results of isoprenoid quinone analyses provided evidence that nocardiae can be distinguished from all other actinomycete taxa on the basis of their characteristic menaquinone profiles. Nocardiae typically contain hexahydrogenated menaquinones with eight isoprene units in which the two end units are cyclized.

A phylogenetic analysis of the genus Saccharomonospora conducted with 16S rRNA gene sequences.

Abstract: Nearly complete sequences of 16S rRNA genes of representative strains of the genus Saccharomonospora were determined following the isolation and cloning of the amplified genes. The sequences were aligned with those of representatives of the family Pseudonocardiaceae, and a phylogenetic tree was inferred by the neighbor-joining method. The genus Saccharomonospora formed a distinct clade within the evolutionary radiation encompassed by the family Pseudonocardiaceae. The average nucleotide similarity value found between the type strains of the four validly described Saccharomonospora species was 97.5% ± 1.0%. The most distant relationship was found between Saccharomonospora azurea and Saccharomonospora viridis K73 (96.3% similarity). In contrast, Saccharomonospora azurea K161 and “Saccharomonospora caesia” K163 had identical 16S rRNA gene sequences. The nucleotide sequence data suggest that the genus Saccharomonospora contains several new centers of variation.