---

期 刊 ：植物保护学报 2009年

关键词：嗜铁素；拮抗作用；枯草芽孢杆菌；质谱分析；嗜铁素分析；

Keywords:siderophore, antagonism, Bacillus subtilis, electrospray ionization mass spectrometry, DHB,

摘 要 ：采用CAS检测平板法,从海南岛橡胶树根际土壤分离到一株产嗜铁素能力较强的菌株CAS15,并通过室内平板对峙试验研究CAS15对15个常见病害病原菌的拮抗作用。结果显示,CAS15具有较强的拮抗作用,其菌液过滤液对病原菌抑制作用较强,抑制率为19.26%~94.07%。根据菌株形态特征、培养性状、生理生化特性及16S rDNA序列分析结果,将CAS15鉴定为枯草芽孢杆菌Bacillus subtilis。质谱分析和嗜铁素分析表明,CAS15产生的嗜铁素为儿茶酚型嗜铁素(DHB-Gly-Thr)₃,分子质量为881.25,且嗜铁素的产生受到铁离子的抑制,当培养基中含有50μmol/L FeCl₃时,其吸光度比值(OD₅₁₀/OD₆₀₀)为0.001~0.01。

Abstract:CAS15, which produced large size of orange halo, was isolated from the rhizosphere soil of rubber tree in Hainan by chrome azurol sulphonate (CAS) agar plate assay. The duel-culture tests showed that CAS15 had strong antagonism against the 15 selected fungal pathogens, and its cell-free supernatant significantly inhibited the growth of the 15 pathogens, with the inhibiting rate of 19.26%-94.07%. According to the characteristics of morphological, cultural, physiological and biochemical, as well as 16S rDNA sequencing, CAS15 was identified as Bacillus subtilis.And then the type of siderophore it produced and the siderophore productivity were analyzed by ESI-MS assay and DHB (G) assay respectively. The results showed that the siderophore produced by CAS15 was catecholic siderophore 2, 3-dihydroxybenzoate-glycine-threonine trimeric ester bacillibactin, with the calculated mass of 881.25, and the siderophore productivity was significantly inhibited by iron. When there was 50 μmol/L FeCl₃ in the medium, the OD₅₁₀/OD₆₀₀ value is 0.001-0.01.

---