Discovering a mitochondrion-localized BAHD acyltransferase involved in calystegine biosynthesis and engineering the production of 3β-tigloyloxytropane

• Published in: Nature communications 2024-04, Vol.15 (1), p.3623-3623, Article 3623
• Main Authors: Zeng, Junlan, Liu, Xiaoqiang, Dong, Zhaoyue, Zhang, Fangyuan, Qiu, Fei, Zhong, Mingyu, Zhao, Tengfei, Yang, Chunxian, Zeng, Lingjiang, Lan, Xiaozhong, Zhang, Hongbo, Zhou, Junhui, Chen, Min, Tang, Kexuan, Liao, Zhihua
• Format: Article
• Language: English
• Subjects: 13/106; 38/35; 38/39; 38/70; 38/89; 631/449/2667; 631/45/603; 631/61/318; 631/92/60/1172; 82/80; 82/83; Acyltransferase; Acyltransferases - genetics; Acyltransferases - metabolism; Atropa belladonna; Biosynthesis; E coli; Enzymology; Escherichia coli - genetics; Escherichia coli - metabolism; Esterification; Humanities and Social Sciences; Mitochondria; Mitochondria - enzymology; Mitochondria - metabolism; Molecular docking; Molecular Docking Simulation; multidisciplinary; Mutagenesis, Site-Directed; Neurodegenerative diseases; Nicotiana - genetics; Nicotiana - metabolism; Plant Proteins - genetics; Plant Proteins - metabolism; Science; Science (multidisciplinary); Site-directed mutagenesis; Tobacco; Tropane alkaloids; Tropanes - metabolism
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-024-47968-0

Solanaceous plants produce tropane alkaloids (TAs) via esterification of 3 α - and 3 β -tropanol. Although littorine synthase is revealed to be responsible for 3 α -tropanol esterification that leads to hyoscyamine biosynthesis, the genes associated with 3 β -tropanol esterification are unknown. Here, we report that a BAHD acyltransferase from Atropa belladonna , 3 β -tigloyloxytropane synthase (TS), catalyzes 3 β -tropanol and tigloyl-CoA to form 3 β -tigloyloxytropane, the key intermediate in calystegine biosynthesis and a potential drug for treating neurodegenerative disease. Unlike other cytosolic-localized BAHD acyltransferases, TS is localized to mitochondria. The catalytic mechanism of TS is revealed through molecular docking and site-directed mutagenesis. Subsequently, 3 β -tigloyloxytropane is synthesized in tobacco. A bacterial CoA ligase (PcICS) is found to synthesize tigloyl-CoA, an acyl donor for 3 β -tigloyloxytropane biosynthesis. By expressing TS mutant and PcICS, engineered Escherichia coli synthesizes 3 β -tigloyloxytropane from tiglic acid and 3 β -tropanol. This study helps to characterize the enzymology and chemodiversity of TAs and provides an approach for producing 3 β -tigloyloxytropane. A mitochondrion-localised BAHD acyltransferase (3 β -tigloyloxytropane synthase, TS) from Atropa belladonna is responsible for the formation of 3 β -tigloyloxytropane, the key intermediate in calystegine biosynthesis.