Data_Sheet_3_The novel distribution of intracellular and extracellular flavonoids produced by Aspergillus sp. Gbtc 2, an endophytic fungus from Ginkgo biloba root.FASTA

Here, we reported a Ginkgo endophyte, Aspergillus sp. Gbtc 2, isolated from the root tissue. Its flavonoid biosynthesis pathway was reconstructed, the effect of phenylalanine on the production of flavonoids was explored, and the flavonoid metabolites were identified with the high-resolution Liquid chromatography–mass spectrometry (LC–MS). Some essential genes were annotated to form the upstream of the complete biosynthesis pathway, indicating that Aspergillus sp. Gbtc 2 has the ability to synthesize the C6–C3–C6 flavonoid monomers. HPLC results showed that adding an appropriate amount of phenylalanine could promote the production of flavonoids by Aspergillus Gbtc 2. LC–MS results depicted a significant difference in many flavonoids between intracellularly and extracellularly. Most of the flavonoids gathered in the cell contained glycosylation groups, while almost all components with multiple hydroxyls showed much higher concentrations extracellularly than intracellularly; they likely have different biological functions. A variety of these substances can be mapped back to the pathway pattern of flavonoid biosynthesis and prove the ability of flavonoid production once again. This study expanded the information on flavonoid biosynthesis in Aspergillus and provided a solid theoretical basis for developing the fungi into genetically engineered strains undertaking flavonoid industrialized production.

本研究报道了一株从银杏根组织中分离得到的银杏内生真菌——曲霉属（Aspergillus sp.）Gbtc 2菌株。我们重构了该菌株的黄酮类化合物生物合成途径，探讨了苯丙氨酸对黄酮类化合物合成的影响，并采用高分辨液相色谱-质谱联用（high-resolution Liquid chromatography–mass spectrometry，LC-MS）技术对黄酮类代谢物进行了鉴定。注释得到的部分关键基因构成了完整生物合成途径的上游区段，表明曲霉属Gbtc 2菌株具备合成C6–C3–C6型黄酮单体的能力。高效液相色谱（High Performance Liquid Chromatography，HPLC）结果显示，添加适量苯丙氨酸可促进该菌株合成黄酮类化合物。LC-MS分析结果表明，菌株胞内与胞外的多种黄酮类化合物存在显著差异：多数胞内富集的黄酮类化合物带有糖基化修饰基团，而几乎所有含多羟基的黄酮组分在胞外的浓度均显著高于胞内，推测二者可能具有不同的生物学功能。其中多种物质可匹配黄酮类化合物生物合成途径的代谢图谱，再次验证了该菌株的黄酮合成能力。本研究丰富了曲霉属真菌黄酮类生物合成的相关研究数据，为将该菌株开发为可用于黄酮类化合物工业化生产的基因工程菌株提供了坚实的理论基础。