PDF(Pubmed)
Abstract：
Soil microorganisms with diverse bioactive compounds such as Streptomyces are appreciated as valuable resources for the discovery of eco-friendly fungicides. This study isolated a novel Streptomyces from soil samples collected in the organic green tea fields in South Korea. The isolation process involved antifungal activity screening around 2400 culture extracts, revealing a strain designated as S. collinus Inha504 with remarkable antifungal activity against diverse phytopathogenic fungi. S. collinus Inha504 not only inhibited seven phytopathogenic fungi including Fusarium oxysporum and Aspergillus niger in bioassays and but also showed a control effect against F. oxysporum infected red pepper, strawberry, and tomato in the in vivo pot test. Genome mining of S. collinus Inha504 revealed the presence of the biosynthetic gene cluster (BGC) in the chromosome encoding a polyene macrolide which is highly homologous to the lucensomycin (LCM), a compound known for effective in crop disease control. Through genetic confirmation and bioassays, the antifungal activity of S. collinus Inha504 was attributed to the presence of LCM BGC in the chromosome. These results could serve as an effective strategy to select novel Streptomyces strains with valuable biological activity through bioassay-based screening and identify biosynthetic gene clusters responsible for the metabolites using genome mining approach.
摘要：
具有多种生物活性化合物的土壤微生物如链霉菌被认为是发现生态友好型杀真菌剂的宝贵资源。这项研究从韩国有机绿茶田收集的土壤样品中分离出一种新型链霉菌。分离过程涉及抗真菌活性筛选约2400个培养物提取物，揭示了一种名为S.collinusInha504的菌株，对多种植物病原真菌具有显着的抗真菌活性。S.collinusInha504不仅在生物测定中抑制了7种植物病原真菌，包括尖孢镰刀菌和黑曲霉，而且对尖孢镰刀菌感染的红辣椒也表现出控制作用，草莓,和番茄在体内盆栽试验。S.collinusInha504的基因组挖掘揭示了在编码多烯大环内酯的染色体中存在生物合成基因簇（BGC），该多烯大环内酯与lucensomycin（LCM）高度同源，一种已知能有效控制作物病害的化合物。通过基因确认和生物测定，S.collinusInha504的抗真菌活性归因于染色体中LCMBGC的存在。这些结果可以作为通过基于生物测定的筛选选择具有有价值生物活性的新型链霉菌菌株的有效策略，并使用基因组挖掘方法鉴定负责代谢物的生物合成基因簇。
