蛇足石杉内生真菌产黄青霉菌MT-40中xanthocillin类似物生物合成基因簇的挖掘及鉴定

Mining and identification of a biosynthetic gene cluster producing xanthocillin analogues from Penicillium chrysogenum MT-40, an endophytic fungus of Huperzia serrata

摘要:

Xanthocillin具有显著的抗菌活性，结构中含有独特的异腈基。本文通过对蛇足石杉(Huperzia serrata)内生真菌产黄青霉菌(Penicillium chrysogenum) MT-40基因组的测序分析，利用本地BLAST等生物信息学分析工具挖掘具有合成xanthocillin类似物潜力的基因簇，结合米曲霉(Aspergillus oryzae) NSAR1异源表达技术实现基因簇中关键基因的功能鉴定。结果成功从内生真菌P. chrysogenum MT-40中发现一个合成xanthocillin类似物的生物合成基因簇(命名为for)，for基因簇中的关键生物合成基因forB编码的异腈基合成酶可以催化合成2-formamido-3- (4-hydroxyphenyl) acrylic acid，基因forG编码的P450酶可以催化2-formamido-3-(4-hydroxyphenyl) acrylic acid的二聚化生成xanthocillin类似物N,N'-(1,4-bis (4-hydroxyphenyl) buta-1,3-diene-2,3-diyl) diformamide。本文研究结果为进一步从真菌中发现xanthocillin类似物提供参考。

关键词:异腈类化合物;xanthocillin;米曲霉;蛇足石杉;内生真菌

Abstract:

Xanthocillin is a unique natural product with an isonitrile group and shows remarkable antibacterial activity. In this study, the genome of an endophytic fungus Penicillium chrysogenum MT-40 isolated from Huperzia serrata was sequenced, and the gene clusters with the potential to synthesize xanthocillin analogues were mined by local BLAST and various bioinformatics analysis tools. As a result, a biosynthetic gene cluster (named for) responsible for the biosynthesis of xanthocillin analogues was identified by further heterologous expression of the key genes in Aspergillus oryzae NSAR1. Specifically, the ForB catalyzes the synthesis of 2-formamido-3-(4-hydroxyphenyl) acrylic acid, and the ForG catalyzes the dimerization of 2-formamido-3-(4-hydroxyphenyl) acrylic acid to produce the xanthocillin analogue N,N'-(1,4-bis (4-hydroxyphenyl) buta-1,3-diene-2,3-diyl) diformamide. The results reported here provide a reference for further discovery of xanthocillin analogues from fungi.

Key words:isonitrile compound;xanthocillin;Aspergillus oryzae;Huperzia serrata;endophytic fungi