Caratterizzazione di alcuni geni chiave per la produzione di metaboliti secondari in Passiflora incarnata ed Echinacea angustifolia. In Colture artificiali di piante medicinali.

Phenylalanine ammonia lyase (PAL; E.C.4.3.1.5.) is the gateway from primary metabolism into the important secondary phenylpropanoid metabolism in plant. PAL catalyses the non oxidative elimination of ammonia from L-Phe to give trans-cinnamate, a precursor of numerous phenylpropanoid compounds that fulfil various essential functions as mechanical supports (lignins), as protectans against biotic and biotic stresses, as pigment like the anthocyanins. Because of its key role in secondary phenylpropanoid metyabolism and secondary metabolites, PAL is one of the most extensively studied plant enzymes. A PAL gene, designed PaPAL, was isolated from Passiflora incarnata with a full length cDNA of 2384 nucleotides; a partial cDNA of 1987 nucleotides, named EcPAL, was obtained from Echinacea angustifolia roots. The expression analysis of the two genes revealed that the PaPAL gene is expressed in young leaves at the first stage of development, whilst the EcPAL is expressed only in the roots of Echinacea plants cultivated in hydroponic cultivation . These results indicate that the expression of PAL genes is highly regulated by the culture conditions and stage of development.