1994 Volume 8 Issue 2 Pages 116
The nomenclature of Streptomyces kasugaensis that produces kasugamycin has not been approved taxonomically, although it was approved as one of the Streptomyces hosts in the Japanese guideline for recombinant DNA experiment. In order to establish its taxonomic status, we examined two strains, M338-M1 and MB273-C4, of S. kasugaensis for their taxonomic properties; not only conventional characterization such as morphology and physiology, but also analyses of cell wall type and DNA. Consequently, the following results were obtained.
Both strains, M338-M1 and MB273-C4, developed spiral aerial mycelium which at maturity formed chains of 10∼50 spores with smooth surface. Aerial mass color of their surface growth on agar media was Gray series color. The type of 2,6-diaminopimelic acid in the cell wall was LL-type. These characteristics indicated that they were regarded as Streptomyces. Based on the data obtained, we searched for candidate species that have similar characteristics by the aid of a data base of actinomycetes. It turned out that S. xantholiticus was selected as the one with similarity to the strains of S. kasugaensis. Subsequently, these two strains were compared with S. xantholiticus IMC S-0620 (=ISP 5244) in terms of morphology, physiology, chemical components of cell wall, DNA homology etc. Although detailed data were not elaborated here, there was a big difference allowing to distinguish S. kasugaensis from S. xantholiticus. Furthermore, DNA homology was high (77% or higher) between S. kasugaensis strains, and low (21% or lower) between S. kasugaensis and S. xantholiticus. Another clear difference was observed in the RAPD (random amplified polymorphic DNA) profiles.
Based on these, we propose that Streptomyces kasugaensis can be regarded as an independent or new species.
Details of taxonomic characterization of S. kasugaensis strains will be described in the next volume of ACTINOMYCETOLOGICA.
