Ethylene-controlled Induction of Phenylalanine Ammonia-lyase in Citrus Fruit Peel 1
AUTOR(ES)
Riov, J.
RESUMO
l-Phenylalanine ammonia-lyase (PAL) activity is low in the external layers (flavedo) of intact mature grapefruit peel. Flavedo discs evince upon incubation increasing PAL activity and ethylene production. Light has no effect in enhancing PAL activity in discs. Exogenous ethylene stimulates PAL activity in the flavedo of intact mature grapefruits (half maximum stimulation at 15 ppm); such activity rapidly decreases when fruit is removed from the ethylene containing atmosphere. Carbon dioxide inhibits both ethylene production and PAL activity of discs; exogenous ethylene only partly relieves PAL inhibition. Cycloheximide inhibits both PAL activity and ethylene production by flavedo discs. The same concentration of cycloheximide also inhibits PAL activity of discs in the presence of exogenous ethylene. Protein synthesis seems therefore to be needed at both levels of ethylene evolution and enhancement of PAL activity.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=396138Documentos Relacionados
- Maize phenylalanine ammonia-lyase has tyrosine ammonia-lyase activity.
- Ethylene-enhanced Synthesis of Phenylalanine Ammonia-Lyase in Pea Seedlings 1
- Ethylene-induced Phenylalanine Ammonia-Lyase Activity in Carrot Roots 12
- Induction of Phenylalanine Ammonia-Lyase in Xanthium Leaf Discs: Increased Inactivation in Darkness
- l-Phenylalanine Ammonia-lyase (Maize): Partial Purification and Response to Gibberellic Acid and Cycloheximide of l-Phenylalanine and l-Tyrosine Ammonia-lyase Activities 1
