Mise en évidence ?amines liées à des structures cellulaires chez Nicotiana tabacum et Lycopersicum esculentum

Abstract

Demonstration of amines connected with cellular structures in Nicotiana tabacum and Lycopersicum esculentum. The level of free and bound amines in various tissues of Nicotiana tabacum cv. Xanthi was investigated. After acid hydrolysis of different pellets from ethanol or buffer extractions, three aliphatic polyamines (putrescine, spermidine, spermine) and one aromatic monoamine (tyramine) were found in different proportions according to the nature of the tissue. Roots contain high quantities of insoluble tyramine bound very strongly to cellular structures. On the contrary, there were only traces of bound tyramine in leaves and stem. After extraction and purification of cell structures, tyramine was shown to be bound to one component of the cell wall. Addition of pronase or cellulase to the extract did not break the tyramine complex. In tobacco roots, insoluble tyramine concentration increased with plant development. High content of bound tyramine was also found in Lycopersicum esculentum roots. The possibility that tyramine binds with lignin is discussed.

Polyamines, floral induction and floral development of strawberry (Fragaria ananassa Duch.)

“…Both ODC and ADC are active in plant tissues and their relative contributions to putrescine and polyamine biosynthesis are dependent upon the type of tissue and the developmental process [8,23]. It thus appears that in several plants free polyamines derived through ADC may be involved in juvenile development, while polyamine conjugates derived through ODC may be required for floral initiation and sexual differentiation [4,8, 15,231. In Xanthium strumarium, a short-day plant, exposure of leaves to successive inductive nights resulted in a rise in conjugated polyamines, especially of spermine [8], per unit protein nitrogen.…”

Quantification of polyamine losses during manipulation and assay procedures

“…In a n acidic environment, recovery was considerably reduced by the presence of starch, but it can be markedly improved by adding NaHCO, after the Dns-CI ( (Wolff and Dean, 1987;Led1 et al, 1989) that could block amino group reactivity to Dns-CI. Vallee et al (1983) reported a loss of tyramine (S-lS%) after acidic hydrolysis and the recovery of tyramine was dependent mainly on the polysaccharide titer of the extract. The loss of certain amino acids after protein hydrolysis in the presence of polysaccharides was also reported by Boulangier and Biserte (199).…”

Μελέτη της επίδρασης 6 αμινοξέων, της μυο-ινοσιτόλης, του dikegulac, των πολυαμινών και της μελατονίνης στον μικροπολλαπλασιασμό των υποκειμένων κερασιάς

“…Oι PΑs διανέμονται σε όλα τα βλαστικά και αναπαραγωγικά όργανα των φυτών: ρίζες, μίσχοι, φύλλα, άνθη (γύρη, στήμονες, ύπερους), βρίσκονται στα σπέρματα (έμβρυο και ενδοσπέρμιο), στα σπορόφυτα, στους κονδύλους, στα μεριστώματα, στο ξύλωμα, στο φλοίωμα και στους παρεχγυματικούς ιστούς (Vallee et al, 1983;Felix and Harr, 1987;Evans and Malmberg, 1989). Στα κύτταρα, οι PΑs εντοπίζονται στα χυμοτόπια, δεσμευμένες στον πυρήνα, στα μιτοχόνδρια, στους χλωροπλάπλες, στα ριβοσώματα, στα κυτταρικά τοιχώματα, στις μεμβράνες και είναι παρούσες στο αποπλαστικό υγρό (Goldberg and Perdrizet, 1984;Bagni, 1989;Evans and Malmberg, 1989;Bors et al, 1989;Slocum, 1991b;Bagni and Pistocchi, 1991).…”