Institute of Fundamental Sciences, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand.
Toxins (Basel). 2013 Aug 14;5(8):1422-46. doi: 10.3390/toxins5081422.
The indole-diterpene paxilline is an abundant secondary metabolite synthesized by Penicillium paxilli. In total, 21 genes have been identified at the PAX locus of which six have been previously confirmed to have a functional role in paxilline biosynthesis. A combination of bioinformatics, gene expression and targeted gene replacement analyses were used to define the boundaries of the PAX gene cluster. Targeted gene replacement identified seven genes, paxG, paxA, paxM, paxB, paxC, paxP and paxQ that were all required for paxilline production, with one additional gene, paxD, required for regular prenylation of the indole ring post paxilline synthesis. The two putative transcription factors, PP104 and PP105, were not co-regulated with the pax genes and based on targeted gene replacement, including the double knockout, did not have a role in paxilline production. The relationship of indole dimethylallyl transferases involved in prenylation of indole-diterpenes such as paxilline or lolitrem B, can be found as two disparate clades, not supported by prenylation type (e.g., regular or reverse). This paper provides insight into the P. paxilli indole-diterpene locus and reviews the recent advances identified in paxilline biosynthesis.
吲哚二萜类化合物派烯是由青霉属（Penicillium）合成的一种丰富的次生代谢产物。在 PAX 基因座共鉴定出 21 个基因，其中 6 个先前已被证实具有在派烯生物合成中发挥功能作用。通过生物信息学、基因表达和靶向基因替换分析相结合，确定了 PAX 基因簇的边界。靶向基因替换鉴定出了 7 个基因，即 paxG、paxA、paxM、paxB、paxC、paxP 和 paxQ，它们都对派烯的产生是必需的，另外还有一个基因 paxD，对派烯合成后吲哚环的常规 prenylation 是必需的。两个假定的转录因子 PP104 和 PP105 与 pax 基因没有共同调节，并且基于靶向基因替换，包括双敲除，在派烯产生中没有作用。涉及吲哚二萜类化合物 prenylation 的吲哚二甲基烯丙基转移酶的关系，如派烯或洛替雷姆 B，可以发现有两个不同的分支，这与 prenylation 类型（例如，常规或反向）无关。本文提供了对青霉属吲哚二萜类化合物基因座的深入了解，并回顾了最近在派烯生物合成中确定的进展。
