More than 70% of vascular plant species live in symbiosis with arbuscular mycorrhizal (AM) fungi. In addition to other effects this symbiosis is known for its significance for plant nutrition including iron. Fungal iron mobilization from soil is commonly dependent on siderophores. This study reports on a search for such iron-chelators in root tissue of Tagetes patula nana var. plena colonized by Gigaspora margarita. The AM colonized plants and uninoculated controls were grown under strictly axenic conditions. HPLC analyses of aqueous extracts from plant roots have provided clear evidence for the presence of a rhizoferrin type siderophore, named glomuferrin, in root tissue of mycorrhizal seedlings. Results from HPLC analytical work are seconded by molecular biological data: A BLASTp search revealed that the AM fungal species Gigaspora rosea, Rhizophagus irregularis (formerly Glomus intraradices), Glomus cerebriformis and Diversispora epigea encode a non-ribosomal peptide synthetase (NRPS)-independent siderophore synthase (NIS), which is homologous to the rhizoferrin synthetase of Rhizopus delemar. Thus this study indicates that the biosynthesis of rhizoferrin type siderophores such as glomuferrin (= bis-imidorhizoferrin) may be widespread in the AM symbiosis.

中文翻译：

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植物根组织中的铁载体：由丛枝菌根真菌玛格丽塔玛格丽塔（Gigaspora margarita）定殖的万寿菊（Tagetes patula nana）。

超过70％的维管植物物种与丛枝菌根（AM）真菌共生。除了其他作用外，这种共生还因其对包括铁在内的植物营养的重要性而闻名。从土壤中动员真菌铁通常取决于铁载体。这项研究报告了寻找在Tagetes patula nana var的根组织中寻找这种铁螯合剂的方法。千足莲被玛格丽塔酒（Gigaspora margarita）殖民。AM定植的植物和未接种的对照在严格的缺氧条件下生长。从植物根部提取的水提物的HPLC分析提供了明确的证据，证明在菌根幼苗的根组织中存在根铁蛋白型铁载体，称为gloferferrin。分子生物学数据支持HPLC分析工作的结果：BLASTp搜索显示AM真菌物种Gigaspora rosea，不规则的根瘤菌（以前称为Glomus intraradices），Germus cerebriformis和Diversispora epigea编码一个非核糖体肽合成酶（NRPS）独立的铁载体合成酶（NIS），它与Rhizopus delemar的根铁蛋白合成酶同源。因此，这项研究表明，根铁蛋白型铁载体如gloferferrin（= bis-imidorhizoferferrin）的生物合成可能在AM共生中广泛存在。