[Systematic place of the act nomycetes of the Albidus Krassilnikov, 1970 group].

Detailed studies of the taxonomical characteristics and the complex of produced antibiotics made it possible to establish the identity of Actinomyces albus var. fungatus, Solovieva et Rudaya, 1959 and Actinomyces tumemacerans, Krassilnikov et Koveshnikov, 1962. Both organisms produce a complex of antibiotics comprising albofungin, albonursin, and a polyene antibiotic belonging to the group of tetraenes. The cultures do not belong to the group of verticillate actinomycetes as was believed earlier (Krassilnikov, 1970). The later name, Actinomyces tumemacerans, is more appropriate since the organism described under the name of Act. albus var. fungatus differs sharply from other representatives of Act. albus and therefore cannot be regarded as its variety (nomen confusum). Actinomyces sp. RIA-248 producing albofungin differs from Act. tumemacerans P-42 as well as from Act. albus var. fungatus RIA-247 by the complex of produced antibiotics and other taxonomic properties. Apparently, it should be classed as a new species.