DNA-DNA relatedness between Saccharomonospora species: 'Saccharomonospora caesia' as a synonym of Saccharomonospora azurea

Abstract

Saccharomonospora species were subjected to DNA-DNA relatedness determination to investigate their genetic relationships based on genomic DNA. The levels of DNA-DNA relatedness among the type strains of the four validly described Saccharomonospora species ranged from 18 to 46%, Saccharomonospora viridis KCTC 9156, which was described as 'Saccharomonospora internatus' but later reclassified as a member of S. viridis, showed a similarity level of 90% to S. viridis KCTC 9115(T). Saccharomonospora sp. strain K180 exhibited levels of DNA-DNA relatedness that are indicative of a new species. Saccharomonospora azurea exhibited levels of DNA-DNA homology of 84-95% to 'Saccharomonospora caesia' strains including the type strain. Therefore, on the basis of DNA-DNA relatedness data and taxonomic data described previously, it is proposed that 'S. caesia' should be considered as a synonym of S. azurea.