The search for synonyms among streptomycetes by using SDS-PAGE of whole-cell proteins. Emendation of the species Streptomyces aurantiacus, Streptomyces cacaoi subsp. cacaoi, Streptomyces caeruleus and Streptomyces violaceus.

A collection of 93 Streptomyces reference strains were investigated using SDS-PAGE of whole-cell proteins. Computer-assisted numerical analysis revealed 24 clusters encompassing strains with very similar protein profiles. Five of them grouped several type strains with visually identical patterns. DNA-DNA hybridizations revealed homology values higher than 70% among these type strains. According to the current species concept, it is proposed that Streptomyces albosporeus subsp. albosporeus LMG 19403T is considered as a subjective synonym of Streptomyces aurantiacus LMG 19358T, that Streptomyces aminophilus LMG 19319T is considered as a subjective synonym of Streptomyces cacaoi subsp. cacaoi LMG 19320T, that Streptomyces niveus LMG 19395T and Streptomyces spheroides LMG 19392T are considered as subjective synonyms of Streptomyces caeruleus LMG 19399T, and that Streptomyces violatus LMG 19397T is considered as a subjective synonym of Streptomyces violaceus LMG 19360T.