Biosynthesis of salicylic acid in fungus elicited Catharanthus roseus cells

• Published in: Phytochemistry (Oxford) 2009-03, Vol.70 (4), p.532-539
• Main Authors: Mustafa, Natali R., Kim, Hye Kyong, Choi, Young Hae, Erkelens, Cornelis, Lefeber, Alfons W.M., Spijksma, Gerwin, Heijden, Robert van der, Verpoorte, Robert
• Format: Article
• Language: English
• Subjects: 2,3-Dihydroxybenzoic acid; benozoic acid 2-hydroxylase; biochemical pathways; Biological and medical sciences; Carbon Isotopes; Catharanthus - metabolism; Catharanthus - microbiology; Catharanthus roseus; Catharanthus roseus cell suspension cultures; cell suspension culture; Cells, Cultured; Chemical constitution; cultured cells; Fundamental and applied biological sciences. Psychology; General pharmacology; Hydroxybenzoates - chemistry; Hydroxybenzoates - metabolism; Isochorismate pathway; isochorismate pyruvate-lyase; isochorismate synthase; Medical sciences; Nuclear Magnetic Resonance, Biomolecular; Pharmacognosy. Homeopathy. Health food; Pharmacology. Drug treatments; phenylalanine ammonia-lyase; Phenylalanine pathway; Plant physiology and development; Pythium - physiology; Pythium aphanidermatum; salicylic acid; Salicylic Acid - chemistry; Salicylic Acid - metabolism; Salicylic acid biosynthesis
• ISSN: 0031-9422; 1873-3700
• DOI: 10.1016/j.phytochem.2009.01.009

Feeding experiments using [1- 13C]- d-glucose to Catharanthus roseus (L.) G.Don cell suspension cultures were performed in order to study the salicylic acid (SA) biosynthetic pathway and that of 2,3-dihydroxybenzoic acid (2,3-DHBA) as a comparison. Relatively high- and non-symmetrical enrichment ratios at C-2 and C-6, and a lower enrichment ratio at C-7 were observed in both SA and 2,3-DHBA detected by 13C NMR inverse gated spectrometry leading to the conclusion that the isochorismate pathway is responsible for the biosynthesis of both compounds rather than the phenylpropanoid pathway. Feeding experiments using [1- 13C]- d-glucose to Catharanthus roseus (L.) G.Don cell suspension cultures followed by elicitation with Pythium aphanidermatum extract were performed in order to study the salicylic acid (SA) biosynthetic pathway and that of 2,3-dihydroxybenzoic acid (2,3-DHBA) as a comparison. A strongly labeled C-7 and a symmetrical partitioning of the label between C-2 and C-6 would occur if SA was synthesized from phenylalanine. In case of the isochorismate pathway, a relatively lower incorporation at C-7 and a non-symmetrical incorporation at C-2 and C-6 would be obtained. Relatively, high- and non-symmetrical enrichment ratios at C-2 and C-6, and a lower enrichment ratio at C-7 were observed in both SA and 2,3-DHBA detected by 13C NMR inverse gated spectrometry leading to the conclusion that the isochorismate pathway is responsible for the biosynthesis of both compounds. However, different enrichment ratios of the labeled carbons in SA and 2,3-DHBA indicate the use of different isochorismate pools, which means that their biosynthesis is separated in time and/or space.