Submitted to: Antonie Van Leeuwenhoek
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/6/2011
Publication Date: 1/30/2012
Citation: Labeda, D.P., Goodfellow, M., Brown, R., Ward, A.C., Lanoot, B., Vanncanneyt, M., Swings, J., Kim, S.B., Liu, Z., Chun, J., Tamura, T., Oguchi, A., Kikuchi, T., Kikuchi, H., Nishii, T., Tsuji, K., Yamaguchi, Y., Tase, A., Takahashi, M., Sakane, T., Suzuki, K.I., Hatano, K. 2012. Phylogenetic study of the species within the family Streptomycetaceae. Antonie Van Leeuwenhoek. 101(1):73-104. Interpretive Summary: Streptomyces species represent a significant portion of the microbial component of soils, where they facilitate nutrient cycling and have been the major source of important antibiotics for human and animal health, as well as causative agents of certain plant diseases. Species are difficult to identify because there are more than 500 described in the literature. The phylogenetic relationships among all of the species in this genus as well as closely related genera were determined from the sequence of the 16S ribosomal RNA gene and were largely consistent with morphological and physiological differences previously used in the classification of these bacteria. These data provided support for reduction in the number of recognized species by consolidating groups of highly related species under a single species name. These results, and the associated datasets, will facilitate the identification of unknown isolates and recognition of new species of interest by researchers in ecology, medicine, plant pathology, and biotechnology.
Technical Abstract: Species of the genus Streptomyces, which constitute the vast majority of taxa within the family Streptomycetaceae, are a predominant component of the microbial population in soils throughout the world and have been the subject of major isolation and screening efforts over the years because they are a major source of commercially and medically important secondary metabolites. Taxonomic characterization of Streptomyces strains has been a challenge due to the large number of described species, greater than any other microbial genus, resulting from academic and industrial activities. The methods used for characterization have evolved through several phases over the years from those based largely on morphological observations, to subsequent classifications based on numerical taxonomic analyses of standardized sets of phenotypic characters and, most recently, to the use of molecular phylogenetic analyses of gene sequences. The present phylogenetic study examines almost all described species (615 taxa) within the family Streptomycetaceae based on 16S rRNA gene sequences and illustrates the species diversity within this family, which is observed to contain 130 statistically-supported clades, as well as many unsupported and single member clusters. Many of the clades observed correlate well with earlier morphological and numerical taxonomic studies, but it is apparent that insufficient variation is present in the 16S rRNA gene sequence within the species of this family to permit bootstrap-supported resolution of relationships between individual clusters.