MUREIDOMYCINS A-D, NOVEL PEPTIDYLNUCLEOSIDE ANTIBIOTICS WITH SPHEROPLAST FORMING ACTIVITY

I. TAXONOMY, FERMENTATION, ISOLATION AND PHYSICO-CHEMICAL PROPERTIES

Abstract

A strain of actinomycetes identified as Streptomyces flavidovirens produced new antibiotics, mureidomycins (MRD's) A-D, specifically active against Pseudomonas aeruginosa. They were isolated from the culture filtrate by successive column chromatographies such as Amberlite XAD-2 and CG-50, Whatman DE-52 and Toyopearl HW-40. They were amphoteric white powders and soluble in methanol and water. Their molecular weights and molecular formulae in parentheses were 840 (C₃₈H₄₈N₈O₁₂S), 842 (C₃₈H₅₀N₈O₁₂S), 897 (C₄₀H₅₁N₉O₁₃S) and 899 (C₄₀H₅₃N₉O₁₃S), respectively. m-Tyrosine and two unknown substances were detected by amino acid analyses as their common constituents. MRD's A and C contained uracil but MRD's B and D dihydrouracil instead of uracil.