Reconstitution of a fungal meroterpenoid biosynthesis reveals the involvement of a novel family of terpene cyclases


Meroterpenoids are hybrid natural products of both terpenoid and polyketide origin. We identified a biosynthetic gene cluster that is responsible for the production of the meroterpenoid pyripyropene in the fungus Aspergillus fumigatus through reconstituted biosynthesis of up to five steps in a heterologous fungal expression system. The cluster revealed a previously unknown terpene cyclase with an unusual sequence and protein primary structure. The wide occurrence of this sequence in other meroterpenoid and indole–diterpene biosynthetic gene clusters indicates the involvement of these enzymes in the biosynthesis of various terpenoid-bearing metabolites produced by fungi and bacteria. In addition, a novel polyketide synthase that incorporated nicotinyl-CoA as the starter unit and a prenyltransferase, similar to that in ubiquinone biosynthesis, was found to be involved in the pyripyropene biosynthesis. The successful production of a pyripyropene analogue illustrates the catalytic versatility of these enzymes for the production of novel analogues with useful biological activities.

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Figure 1: Representative fungal meroterpenoids and their biological activities.
Figure 2: Proposed biosynthetic pathway of pyripyropene A (9) in A. fumigatus.
Figure 3: The pyripyropene biosynthetic gene cluster (pyr cluster) identified from A. fumigatus.
Figure 4: Products isolated from coexpression experiments.
Figure 5: Functional analyses of Pyr4 in vitro.
Figure 6: A novel meroterpenoid (12) formed through HPhPO (11) from benzoic acid by the pyripyropene biosynthetic machinery.


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We thank T.S. Jeong for providing the pyripyropene-producing strain, and K. Gomi and K. Kitamoto for their support in fungal transformation and expression. A part of this work was supported financially by a Grant-in-Aid for Young Scientists (B) (No. 21710222) from the Japan Society for the Promotion of Science (JSPS) and The Mochida Memorial Foundation for Medical and Pharmaceutical Research to T.K., a Grant-in-Aid for Scientific Research (A) (No. 20241049) to Y.E. from JSPS, a Grant-in-Aid for JSPS Fellows to T.I. from JSPS and a Grant-in-Aid for Scientific Research on Priority Areas ‘Applied Genomics’ to I.F. from the Ministry of Education, Culture, Sports, Science and Technology of Japan.

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T.I., Y.E. and T.K. conceived and designed the experiments, T.I., K.T. and Y.M. performed the experiments, T.I., K.T., Y.M., I.A., Y.E. and T.K. analysed the data, I.F. contributed the fungal expression system and T.I., Y.E. and T.K. co-wrote the paper.

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Correspondence to Tetsuo Kushiro.

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Itoh, T., Tokunaga, K., Matsuda, Y. et al. Reconstitution of a fungal meroterpenoid biosynthesis reveals the involvement of a novel family of terpene cyclases. Nature Chem 2, 858–864 (2010).

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