为了研究海洋灰绿曲霉中抗肿瘤聚酮化合物灰绿霉素A的生物合成机制,需获得相关的聚酮合酶基因簇。根据灰绿霉素A合成途径推断,该化合物母核由非还原型PKS(NR-pKS)催化合成,本文使用LC系列简并引物得到灰绿曲霉中NR—PKS基因片段,再通过基因走读技术得到22.8kb的DNA序列,其含有7个完整的开放阅读框。通过BLAST分析,序列中包含1个NR—PKS编码基因,全长8451bp,命名为Agpks1。AgPks1与烟曲霉PksP、黑曲霉Alb1有很高的同源性。该工作对研究Agpks1对灰绿霉素A或其他聚酮产物合成的催化机制具有重要意义。
It is critical to identify the polyketide synthase (PKS) gene cluster to clarify the biosynthetic mechanism of antitumor polyketide aspergiolide A, which was deduced to be catalyzed non-reduced PKS (NR-PKS) from marine Aspergillus glaucus. In this study, a NR-PKS nucleotide sequence was first obtained using the LC primers. A full sequence of its gene clusters (22.8 kb) was harvested by genome walking, which contains 70RFs by BLAST analysis. Among them, a NR-PKS gene with full length of 8 451 bp was identified by BLAST and designated as Agpksl. The AgPksl showed high homology to Aspergillus furnigatus PksP and Aspergillus niger Albl. This work provides enlightenment for analyzing the functions of Agpksl in biosynthetic mechanism of aspergiolide A or other polyketides produced by Aspergillus glaucus.