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Updated: Oct 31, 2025
Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs
Published on: January 17, 2020
Understanding and Engineering the Stereoselectivity of Humulene Synthase
Carsten Schotte1, Peer Lukat2, Adrian Deuschmann1
1Institute for Organic Chemistry and BMWZ, Leibniz Universität Hannover, Schneiderberg 38, 30167, Hannover, Germany.
Abstract:
The non-canonical terpene cyclase AsR6 is responsible for the formation of 2E,6E,9E-humulene during the biosynthesis of the tropolone sesquiterpenoid (TS) xenovulene A. The structures of unliganded AsR6 and of AsR6 in complex with an in crystallo cyclized reaction product and thiolodiphosphate reveal a new farnesyl diphosphate binding motif that comprises a unique binuclear Mg2+ -cluster and an essential K289 residue that is conserved in all humulene synthases involved in TS formation. Structure-based site-directed mutagenesis of AsR6 and its homologue EupR3 identify a single residue, L285/M261, that controls the production of either 2E,6E,9E- or 2Z,6E,9E-humulene. A possible mechanism for the observed stereoselectivity was investigated using different isoprenoid precursors and results demonstrate that M261 has gatekeeping control over product formation.
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