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Updated: Mar 6, 2026

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
β-Amyrin biosynthesis: catalytic mechanism and substrate recognition
1Graduate School of Science and Technology and Department of Applied Biological Chemistry, Faculty of Agriculture, Niigata University, Ikarashi 2-8050, Nishi-ku, Niigata 950-2181, Japan. hoshitsu@agr.niigata-u.ac.jp.
Oxidosqualene cyclases (OSCs) generate diverse sterols and triterpenoids. This review details advances in understanding beta-amyrin synthase, comparing its mechanism and substrate recognition to related enzymes like lanosterol synthase and squalene-hopene cyclase.
Area of Science:
- Biochemistry
- Enzymology
- Natural Product Biosynthesis
Background:
- Oxidosqualene cyclases (OSCs) catalyze stereospecific polycyclization reactions, forming diverse sterols and triterpenoids.
- Approximately 150 distinct carbon frameworks are generated by OSCs.
- While squalene-hopene cyclase (SHC) and lanosterol synthase (LaS) are well-studied, beta-amyrin synthase research has historically lagged.
Purpose of the Study:
- To review recent advances in beta-amyrin biosynthetic studies.
- To outline the catalytic mechanism and substrate recognition of beta-amyrin synthase.
- To compare beta-amyrin synthase with LaS and SHC, highlighting unique features.
Main Methods:
- Site-directed mutagenesis studies.
- Substrate analog experiments.
- Comparative analysis of enzyme mechanisms.
Main Results:
- Detailed insights into the catalytic mechanism of beta-amyrin synthase.
- Characterization of substrate recognition properties.
- Identification of key differences and similarities between beta-amyrin synthase, LaS, and SHC.
Conclusions:
- Significant progress has been made in understanding beta-amyrin synthase function.
- Beta-amyrin synthase exhibits distinct features compared to LaS and SHC.
- This review provides a comprehensive comparison of these crucial plant enzymes.
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