RESUMO
This paper describes a bioassay method for the determination of ansamitocin titers. A fungal strain sensitive to ansamitocin was classified to the genus Trichoderma based on phylogenetic analysis of its ITS sequence, and designated as Trichoderma CPCC 400749. PDA plates of Trichoderma CPCC 400749 were prepared to assay ansamitocin titers of Actinosynnema pretiosum ATCC 31565. The titers were consistent with those determined by HPLC. The bioassay method may have the potential use in high-throughput screening for Actinosynnema pretiosum mutants with improved ansamitocin titers.
RESUMO
Chuangxinmycin (CM) from Actinoplanes tsinanensis was an antibiotic discovered by Chinese scientists about 40 years ago. It contains a new heterocyclic system of indole fused with dihydrothiopyran, whose biosynthetic mechanism remains unclear. CM is used as an oral medicine in the treatment of bacterial infections in China. The simple structure makes CM as an attractive candidate of structure modification for improvement of antibacterial activity. Recently, we analyzed the secondary metabolites of Actinoplanes tsinanensis CPCC 200056, a CM producing strain, as a natural CM analogue. We discovered the first natural CM analogue 3-demethylchuangxinmycin (DCM) as a new natural product. Compared to CM, DCM exhibited a much weaker activity in the inhibition of the bacterial strains tested. The finding provides valuable information for the structure-activity relationship in the biosynthesis of CM.
Assuntos
Antibacterianos , Química , China , Indóis , Química , Micromonosporaceae , Química , Relação Estrutura-AtividadeRESUMO
Chuangxinmycin (CM) from Actinoplanes tsinanensis was an antibiotic discovered by Chinese scientists about 40 years ago. It contains a new heterocyclic system of indole fused with dihydrothiopyran, whose biosynthetic mechanism remains unclear. CM is used as an oral medicine in the treatment of bacterial infections in China. The simple structure makes CM as an attractive candidate of structure modification for improvement of antibacterial activity. Recently, we analyzed the secondary metabolites of Actinoplanes tsinanensis CPCC 200056, a CM producing strain, as a natural CM analogue. We discovered the first natural CM analogue 3-demethylchuangxinmycin (DCM) as a new natural product. Compared to CM, DCM exhibited a much weaker activity in the inhibition of the bacterial strains tested. The finding provides valuable information for the structure-activity relationship in the biosynthesis of CM.