The programming role of trans-acting enoyl reductases during the biosynthesis of highly reduced fungal polyketides
The programming role of trans-acting enoyl reductases during the biosynthesis of highly reduced fungal polyketides
复制标题
DOI：
10.1039/c1sc00023c
复制
发表时间：
2011-01-01
期刊：
影响因子：
8.4
通讯作者：
Lazarus, Colin M.
中科院分区：
文献类型：
--
作者：
Heneghan, Mary N.;Yakasai, Ahmed A.;Lazarus, Colin M.
从球孢白僵菌992.05中分离到一个新的聚酮合酶非核糖体肽合成酶（PKS-NRPS）基因簇。该簇编码负责新的2-吡啶酮去甲基巴西宁（DMB）的生物合成的酶。DMB在结构上与来自B的tenellin相关。bassiana 110.25，但在链长和甲基化程度上不同。尽管存在这些编程差异，但20 kb DMB生物合成基因簇与tenellin基因簇具有90%的序列同一性。PKS-NRPS基因dmbS的沉默导致DMB生产的完全丧失。dmbS与其同源的反式作用烯酰还原酶基因dmbC在黑曲霉中共表达，产生了生物合成途径中第一个可分离的前体predesmethylbassianin A。dmbS与tenellin反式作用烯酰还原酶基因tenC的表达也导致了前去甲基bassianin A的产生。tenS（tenellin PKS-NRPS）与dmbC的共表达产生了pretenellin A。这些结果表明，tenS和dmbS编码的PKS-NRPS包含聚酮生物合成的程序，而反式作用ER似乎控制程序的保真度。表达一种杂合合成酶，其中腱蛋白合成酶的PKS与来自DMBS的NRPS融合，产生原腱蛋白A至C，表明NRPS不作为影响PKS程序的选择看门人。
A novel polyketide synthase nonribosomal peptide synthetase (PKS-NRPS) gene cluster was isolated from Beauveria bassiania 992.05. The cluster encodes the enzymes responsible for the biosynthesis of the new 2-pyridone desmethylbassianin (DMB). DMB is structurally related to tenellin from B. bassiana 110.25 but it differs in chain length and degree of methylation. Despite these programming differences the 20 kb DMB biosynthetic gene cluster has 90% sequence identity to the tenellin gene cluster. Silencing of the PKS-NRPS gene, dmbS, resulted in total loss of DMB production. Co-expression of dmbS in Aspergillus oryzae with its cognate trans-acting enoyl reductase gene, dmbC, produced predesmethylbassianin A, the first isolable precursor in the biosynthetic pathway. Expression of dmbS with the tenellin trans-acting enoyl reductase gene, tenC, also resulted in the production of predesmethylbassianin A. Co-expression of tenS, the tenellin PKS-NRPS, with dmbC produced pretenellin A. These results show that the tenS and dmbS encoded PKS-NRPS contains the programme for polyketide biosynthesis, while the trans-acting ERs appear to control the fidelity of the programme. Expression of a hybrid synthetase in which the PKS of the tenellin synthetase was fused to the NRPS from DMBS produced prototenellins A to C, indicating that the NRPS does not act as a selecting gatekeeper to affect the PKS programme.