Fusarium wilt is caused by the soil-inhabiting fungus Fusarium oxysporum ff. spp. and is one of the most devastating plant diseases, resulting in losses and decreasing the quality and safety of agricultural crops. We recently reported the structures and biochemical properties of two biotin-binding proteins, streptavidin C1 and C2 (isolated from Streptomyces cinnamonensis strain KPP02129). In the present study, the potential of the biotin-binding proteins as antifungal agent for Fusarium wilt pathogens was investigated using recombinant streptavidin C1 and C2. The minimum inhibitory concentration of streptavidin C2 was found to be 16 µg ml^–1 for inhibiting the mycelial growth of F. oxysporum f.sp. cucumerinum and F. oxysporum f.sp. lycopersici, while that of streptavidin C1 was found to be 64 µg ml^–1. Compared with the nontreated control soil, the population density of F. oxysporum f.sp. lycopersici in the soil was reduced to 49·5% and 39·6% on treatment with streptavidin C1 (500 µg ml^–1) and C2 (500 µg ml^–1), respectively. A greenhouse experiment revealed that Fusarium wilt of tomato plants was completely inhibited on soil drenching using a 50-ml culture filtrate of the streptavidin-producing strain KPP02129.

中文翻译：

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链霉亲和素 C1 和 C2 对引起枯萎病的病原体的抗真菌活性

枯萎病是由土壤中的真菌尖孢镰刀菌ff 引起的。属 并且是最具破坏性的植物病害之一，造成损失并降低农作物的质量和安全。我们最近报道了两种生物素结合蛋白链霉亲和素 C1 和 C2（从肉桂链霉菌菌株 KPP02129 中分离）的结构和生化特性。在本研究中，使用重组链霉亲和素 C1 和 C2 研究了生物素结合蛋白作为枯萎病病原体抗真菌剂的潜力。发现链霉亲和素 C2 的最小抑制浓度为 16 µg ml ^–1，用于抑制F菌丝体生长。尖孢菌黄瓜和F . 尖孢菌 lycopersici，而链霉亲和素 C1 的含量为 64 µg ml ^–1。与未处理的对照土壤相比，F的种群密度。尖孢菌 用链霉亲和素 C1 (500 µg ml ^–1 ) 和 C2 (500 µg ml ^–1 )处理后，土壤中的番茄红素分别减少到 49·5% 和 39·6% 。一项温室实验表明，使用 50 毫升产链霉亲和素菌株 KPP02129 的培养滤液，土壤浸透后番茄植物的枯萎病被完全抑制。