UK-63, 052 COMPLEX, NEW QUINOMYCIN ANTIBIOTICS FROM STREPTOMYCES BRAEGENSIS SUBSP. JAPONICUS; TAXONOMY, FERMENTATION, ISOLATION, CHARACTERISATION AND ANTIMICROBIAL ACTIVITY

Abstract

UK-63, 052 complex, a new group of quinomycin-like antibiotics comprising UK-63, 052 (factor A), UK-63, 598 (factor C), UK-65, 662 (factor B) and several uncharacterised minor components, is produced by a new subspecies of the genus Streptomyces for which the name Streptomyces braegensis Dietz subsp. japonicus, is proposed. The strain, N617-29, is characterised by a negative melanin reaction, grey aerial mycelium, spiral spore chains and smooth or slightly warty spores. Structure determination has identified UK-63, 052, C₅₆H₆₈N₁₀O₁₄S₂, UK-63, 598, C₅₃H₆₂N₁₀O₁₄S₂ and UK-65, 662, C₅₅H₆₆N₁₀O₁₄S₂ as quinaldic acid substituted quinomycins with unusual bridgehead sulfur substitution as shown in Fig. 3.