Planta Med 2005; 71(3): 249-253
DOI: 10.1055/s-2005-837825
Original Paper
Biochemistry and Molecular Biology
© Georg Thieme Verlag KG Stuttgart · New York

Molecular Cloning, Expression and Characterization of Hyoscyamine 6β-Hydroxylase from Hairy Roots of Anisodus tanguticus

Tao Liu1 , Ping Zhu1 , Ke-di Cheng1 , Chao Meng1 , Hui-xia He1
  • 1Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, P. R. China
Further Information

Publication History

Received: May 27, 2004

Accepted: October 9, 2004

Publication Date:
15 March 2005 (online)

Abstract

Anisodus tanguticus, one of the indigenous Chinese ethnological medicinal plants of the Solanaceae, produces anticholinergic alkaloids such as hyoscyamine, 6β-hydroxyhyoscyamine and scopolamine. Hyoscyamine 6β-hydroxylase (H6H), a key enzyme in the biosynthetic pathway of scopolamine, catalyzes the hydroxylation of hyoscyamine and epoxide formation from 6β-hydroxyhyoscyamine to generate scopolamine. A full-length cDNA of H6H has been isolated from A. tanguticus hairy roots. Nucleotide sequence analysis of the cloned cDNA revealed an open reading frame of 1035 bp encoding 344 amino acids with high homology to other known H6Hs. The equivalent amino acid sequence shows a typical motif of 2-oxoglutarate-dependent dioxygenase. The A. tanguticus H6H was expressed in Escherichia coli and purified for enzyme function analysis. This study characterized the recombinant AtH6H and showed it could generate scopolamine from hyoscyamine.

References

Prof. Ke-di Cheng

Institute of Materia Medica

Chinese Academy of Medical Sciences and Peking Union Medical College

# 1 Xian Nong Tan Street

Beijing 100050

P. R. China

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Email: chengkd@imm.ac.cn