ABSTRACT
The cultivation of strains of the genus Streptosporangium in batch fermentations demonstrated that the optimal conditions for secondary metabolite production are completely different to those of the closely related genus Streptomyces. The dissolved oxygen tension (pO(2)) was identified as an important parameter for optimal production of secondary metabolites in submerged cultures. Extreme variations of this parameter by changes in aeration (gas flow), agitation system and stirrer speed showed a tremendous impact in production yields of all investigated strains. Finally, a 20-fold increase in productivity was observed by conditions of controlled oxygen excess compared to optimal fermentation conditions for Streptomyces strains.
Subject(s)
Actinomycetales/metabolism , Fermentation , OxygenABSTRACT
A blue secondary metabolite complex, named kyanomycin (2), in addition to epsilon-rhodomycinone (1), was detected in the mycelium extract of Nonomuria sp. NN 22303 by HPLC-diode array and HPLC-electrospray mass spectrometry screening. The chemical structures of the novel compounds were determined to be unusual anthracycline-phosphatidylethanolamine hybrids by spectroscopic and chemical degradation experiments.
Subject(s)
Actinomycetales/chemistry , Anthracyclines/chemistry , Anthracyclines/isolation & purification , Phospholipids/chemistry , Anthracyclines/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Chromatography, High Pressure Liquid , Microbial Sensitivity Tests , Spectrum AnalysisABSTRACT
The kanchanamycins, a group of novel 36-membered polyol macrolide antibiotics were detected in the culture filtrate and mycelium of Streptomyces olivaceus Tü 4018 by HPLC-diode-array and HPLC-electrospray-mass-spectrometry screening. The compounds show antibacterial and antifungal activities, and are especially effective against Pseudomonas fluorescens. Besides the kanchanamycin complex, strain Tü 4018 produces the 42-membered macrolactones, oasomycin A and desertomycin A, as well as tryptophan-dehydrobutyrine diketopiperazine and daidzein.
Subject(s)
Anti-Bacterial Agents/isolation & purification , Fermentation , Streptomyces/metabolism , Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Chromatography, High Pressure Liquid , Lactones/isolation & purification , Lactones/pharmacology , Macrolides , Streptomyces/classificationABSTRACT
Kanchanamycins are a new group of polyol macrolide antibiotics isolated from Streptomyces olivaceus Tü 4018. They all share a common bicyclic carbon skeleton formed by a 36-membered lactone ring and a 6-membered hemiacetal ring. A feature unusual for that class of macrolides is the terminal urea moiety observed in kanchanamycin A. The structures of the kanchanamycins were determined by electrospray MS and modern 2D NMR techniques. Due to substantial overlap of the signals intensive use of inverse detected heteronuclear correlation experiments (HSQC, HMBC, 2D-HSQC-TOCSY) was made.