Submitted to: International Journal of Systematic and Evolutionary Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 25, 2010
Publication Date: October 20, 2011
Citation: Labeda, D.P. 2011. Multilocus sequence analysis of phytopathogenic species of the genus Streptomyces. International Journal of Systematic and Evolutionary Microbiology. 61(10):2525-2531. Interpretive Summary: This research genetically compared species of Streptomyces to provide a tool for identification of unknown strains of this bacterium. Streptomyces are major sources of antibiotics used in human and animal health, but are also causative agents of certain plant diseases. They are difficult to identify because of the large number of valid species. Comparison of multiple genes from nine different Streptomyces species associated with potato scab disease confirmed that the species were valid and distinct from each other. Using this comparison method, a number of unidentified isolates from potatoes were also identified as belonging to one of the recognized pathogenic species. The study confirmed that potato scab disease is caused by a number of different species and the sequence data generated and deposited in the public databanks provide a useful tool for identification of field isolates by plant pathologists.
Technical Abstract: The identification and classification of species within the genus Streptomyces is difficult because there are presently 576 validly described species and this number increases every year. The value of the application of multilocus sequence analysis scheme to the systematics of Streptomyces species has been well demonstrated in several recently published papers and thus the sequence fragments of 4 housekeeping genes, atpD, recA, rpoB, and trpB, were determined for the type strains of the 9 known phytopathogenic Streptomyces species, including S. scabiei, S. acidiscabies, S. europaescabiei, S. luridiscabiei, S. niveiscabiei, S. pauciscabiei, S. reticuliscabiei, S. stelliscabiei and S. turgidiscabies and S. ipomoeae. The type strains of 18 other species observed to be phylogenetically near to these based on 16S rRNA gene phylogeny were also included in the study. Phylogenetic analysis of single gene alignments and a concatenated 4-gene alignment demonstrated that the phytopathogenic species are taxonomically distinct from each other in spite of high 16S rRNA gene sequence similarity and provided a tool for the identification of unknown putative phytopathogenic Streptomyces strains to the species level.