ORIGINAL PAPER Overexpression of odc (ornithine decarboxylase) in Datura innoxia enhances the yield of scopolamine Alka Singh • Niraj K. Nirala • Sandip Das • Alka Narula • M. V. Rajam • P. S. Srivastava Received: 3 January 2011 / Revised: 27 April 2011 / Accepted: 29 April 2011 / Published online: 15 May 2011 Ó Franciszek Go ´rski Institute of Plant Physiology, Polish Academy of Sciences, Krako ´w 2011 Abstract Scopolamine is widely used for its anticholin- ergic properties. Because of higher physiological activity and less side effects the world demand of scopolamine is estimated to be ten times greater than other anticholinergic agents, hyoscyamine and atropine. Since natural produc- tion is limited, alternatives are required to boost the pro- duction. We report the introduction of mouse odc gene of polyamine biosynthesis pathway which is also the primary pathway of tropane alkaloids in Datura innoxia. Poly- amines, mainly putrescine, serve as the common metabolite for tropane alkaloids and nicotine. We have overexpressed odc gene to modulate the metabolic flux downstream and eventually achieved higher accumulation of scopolamine in transgenic plants. Among six independent transformed lines one line (O10) produced scopolamine (0.258 lg/g dry weight) almost six times higher than that produced by control plants (0.042 lg/g DW). To our knowledge, this is the first report of odc overexpression in D. innoxia leading to higher scopolamine yield. Keywords Arginine decarboxylase Á Ornithine decarboxylase Á Putrescine N-methyltransferase Á Putrescine Á Polyamine Á Scopolamine Introduction Alkaloids have traditionally been of interest due to their pronounced and various physiological activities in humans and animals. In plants, they have ecochemical functions that are reflected in the defence of plants against patho- genic organisms and herbivores. Of several distinct alka- loids, the most important is tropane alkaloid produced by members of Solanaceae, Erythroxylaceae and Convolvul- aceae. A few genera of Solanaceae, such as Datura, Atropa, Hyoscyamus and Duboisia, produce biologically active tropane alkaloids—hyoscyamine and scopolamine (Christen et al. 1993; Griffing and Lin 2000). These plants have been in use for medicinal, hallucinogenic and poi- sonous properties. Along with semisynthetic derivatives, these alkaloids serve as parasympatholytics that competi- tively antagonize acetylcholine. Scopolamine, hyoscya- mine and its racemic form, atropine, are anticholinergic but differ in their action on the central nervous system. Among all anticholinergic agents, scopolamine is preferred for its ability to cross blood-brain barrier more rapidly and its higher physiological activity. As antimuscarinic drug, it is prescribed for the control of Parkinson’s disease, or as mydriatics, that dilate the pupil of eye to facilitate the surgery. The demand therefore is tenfold higher for sco- polamine, in the form of N-butylbromide (Zhang et al. 2004). Worldwide the main source of production of sco- polamine is Duboisia leaves, which contains 2–4% of total alkaloids, with more than 60% of scopolamine and 30% of hyoscyamine. Accordingly, there has been a long-standing Communicated by B. Zheng. S. Das Á A. Narula Á P. S. Srivastava (&) Department of Biotechnology, Hamdard University, New Delhi 110062, India e-mail: pss410@rediffmail.com Present Address: A. Singh Á N. K. Nirala Program in gene Function and Expression, Umass Medical School, Worcester 01605, USA M. V. Rajam Department of Genetics, Delhi University, South Campus, New Delhi 110021, India 123 Acta Physiol Plant (2011) 33:2453–2459 DOI 10.1007/s11738-011-0787-8