RODRIGUEZ TALOU Julian
congresos y reuniones científicas
PROLINE EFFECTS ON SECONDARY METABOLIC PATHWAYS IN RUBIA TINCTORUM CELL SUSPENSIONS.
QUEVEDO, CARLA; BUSTO, VICTOR; IANONE, FLORENCIA; GIULIETTI1, ANA M. AND RODRIGUEZ TALOU, JULIÁN1.
Congreso; SAIB, XLI Annual Meeting - Sociedad Aregntina de Investigaciones Bioquímicas; 2005
S,ociedad Aregntina de Investigaciones Bioquímicas, SAIB
Proline biosynthesis in plants stimulates the pentose phosphate pathway which results in an increasing carbon flux through the shikimate pathway. Shikimate pathway supplies carbon structures for many secondary metabolic pathways in plants. Chorismate, which is the end product of the shikimate pathway, becomes the branch point for the synthesis of phenylpropanoid and anthraquinones (AQs) in Rubia tinctorum secondary metabolism. We tested the effect of proline addition in plant suspension cultures of R. tinctorum in order to study the competition between the two above mentioned secondary metabolic pathways. Suspension cultures were treated with proline at different concentrations 0.25, 5 and 25 mM. Low proline level (0.25mM) produced an increase on AQs (50%) while high levels of proline ( 5 and 25 mM) showed a significant decrease on AQs accumulation ( 35 % an 50 %) and an increase in phenolics concentration. The increase on phenolic acids content was preceded by an induction on PAL activity. Glucose-6-phosphate dehydrogenase was induced during stationary phase of the growth curve. Suspension cultures treated with proline 5 y 25 mM showed lower levels of Peroxidase activities than the control treatment.