Polyamine metabolism in ripening tomato fruit. I. Identification of metabolites of putrescine and spermidine. [Lycopersicon esculentum Mill]

Journal Article · Thu Nov 01 04:00:00 EST 1990 · Plant Physiology; (USA)

DOI:https://doi.org/10.1104/pp.94.3.1449· OSTI ID:5841633

Rastogi, R; Davies, P J ^[1]

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1. Cornell Univ., Ithaca, NY (USA)

The metabolism of (1,4-{sup 14}C)putrescine and (terminal methylene-{sup 3}H)spermidine was studied in the fruit pericarp (breaker stage) discs of tomato (Lycopersicon esculentum Mill.) cv Rutgers, and the metabolites identified by high performance liquid chromatography and gas chromatography-mass spectrometry. The metabolism of both putrescine and spermidine was relatively slow; in 24 hours about 15% of each amine was metabolized. The {sup 14}C label from putrescine was incorporated into spermidine, {gamma}-aminobutyric acid (GABA), glutamic acid, and a polar fraction eluting with sugars and organic acids. In the presence of gabaculine, a specific inhibitor of GABA:pyruvate transminase, the label going into glutamic acid, sugars and organic acids decreased by 80% while that in GABA increased about twofold, indicating that the transamination reaction is probably a major fate of GABA produced from putrescine in vivo. ({sup 3}H)Spermidine was catabolized into putrescine and {beta}-alanine. The conversion of putrescine into GABA, and that of spermidine into putrescine, suggests the presence of polyamine oxidizing enzymes in tomato pericarp tissues. The possible pathways of putrescine and spermidine metabolism are discussed.

• OSTI ID: 5841633
• Journal Information: Plant Physiology; (USA), Journal Name: Plant Physiology; (USA) Vol. 94:3; ISSN 0032-0889; ISSN PLPHA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINES
AMINO ACIDS
AMINOBUTYRIC ACID
AUTONOMIC NERVOUS SYSTEM AGENTS
CARBON 14 COMPOUNDS
CARBOXYLIC ACIDS
DRUGS
ENZYME ACTIVITY
ENZYME INHIBITORS
FOOD
FRUITS
GLUTAMIC ACID
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
METABOLISM
METABOLITES
NEUROREGULATORS
ORGANIC ACIDS
ORGANIC COMPOUNDS
PHYSIOLOGY
PUTRESCINE
SPERMIDINE
TOMATOES
TRACER TECHNIQUES