Fungal indole alkaloid biogenesis through evolution of a bifunctional reductase/Diels–Alderase
- Univ. of Michigan, Ann Arbor, MI (United States)
- Colorado State Univ., Fort Collins, CO (United States)
- Univ. of California, Los Angeles, CA (United States)
Prenylated indole alkaloids such as the calmodulin-inhibitory malbrancheamides and anthelmintic paraherquamides possess great structural diversity and pharmaceutical utility. Here, we report complete elucidation of the malbrancheamide biosynthetic pathway accomplished through complementary approaches. These include a biomimetic total synthesis to access the natural alkaloid and biosynthetic intermediates in racemic form and in vitro enzymatic reconstitution to provide access to the natural antipode (+)-malbrancheamide. Reductive cleavage of an l-Pro–l-Trp dipeptide from the MalG non-ribosomal peptide synthetase (NRPS) followed by reverse prenylation and a cascade of post-NRPS reactions culminates in an intramolecular [4+2] hetero-Diels–Alder (IMDA) cyclization to furnish the bicyclo[2.2.2]diazaoctane scaffold. Enzymatic assembly of optically pure (+)-premalbrancheamide involves an unexpected zwitterionic intermediate where MalC catalyses enantioselective cycloaddition as a bifunctional NADPH-dependent reductase/Diels–Alderase. Furthermore, the crystal structures of substrate and product complexes together with site-directed mutagenesis and molecular dynamics simulations demonstrate how MalC and PhqE (its homologue from the paraherquamide pathway) catalyse diastereo- and enantioselective cyclization in the construction of this important class of secondary metabolites.
- Research Organization:
- Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
- Sponsoring Organization:
- National Institutes of Health (NIH); National Science Foundation (NSF)
- Grant/Contract Number:
- R01 CA070375; R35 GM118101; R01 DK042303; F32GM122218; R01GM124480; OCI-1053575; AGM-12006; ACB-12002
- OSTI ID:
- 1573393
- Journal Information:
- Nature Chemistry, Vol. 11, Issue 11; ISSN 1755-4330
- Publisher:
- Nature Publishing GroupCopyright Statement
- Country of Publication:
- United States
- Language:
- ENGLISH
Web of Science
Total synthesis of brevianamide A
|
journal | April 2020 |
Fungal-derived brevianamide assembly by a stereoselective semipinacolase
|
journal | May 2020 |
Hot off the press
|
journal | January 2018 |
Hot off the Press
|
journal | January 2020 |
Similar Records
Studies on the biosynthesis of paraherquamide A. Origin of the {beta}-methylproline ring
Biosynthesis of t-Butyl in Apratoxin A: Functional Analysis and Architecture of a PKS Loading Module