Influence of hairy root ecotype and rolC expression in the biotechnological production of bioactive compounds

CARDILLO, ALEJANDRA BEATRIZ; GIULIETTI, ANA MARIA; PALAZON, JAVIER; BONFILL, MERCE

Congreso; 15th European Congress on Biotechnology; 2012

European Federation on Biotechnology

Brugmansia candida is a South American native plant that produces tropane alkaloids, including hyoscyamine and scopolamine which were traditionally used in medicine. Hyoscyamine 6b-hydroxylase and Putrescine N-methyltransferase are key enzymes of the tropane alkaloid pathway. It is proposed that the last one is a flux-limiting of the tropane alkaloid pathway. We have previously reported differences in the alkaloid production and growth kinetics between hairy roots of B. candida ecotypes. The aim of this work was to analyze putrescine and m-putrescine production in Argentinean and Colombian ecotypes in order to determine whether or not are differences at other levels of the biosynthetic pathway. Additionally, rolC gen expression was analyzed to determine its correlation with hairy root growth. It is proposed that rol genes, transferred from Agrobacterium rhizogenes to the plant can stimulate the secondary metabolism besides affecting plant development. The results revealed that the tropane alkaloids biosynthetic pathway of the ecotypes has differences not only at the last steps as was previously reported. A higher accumulation of polyamines measured in Colombian hairy roots suggest that may be a limitation in the enzymatic steps that conducts to the formation of hyoscyamine. Additionaly, rolC gene expression was correlated with an improvement hairy root growth supporting the involvement of rol genes as growth modulators. These findings suggest that metabolic engineering via rolC manipulation may be useful for the development of more efficient B. candida hairy root cultures for biotechnological applications according to the improvement on hairy root growth.