Role of exogenous melatonin in table grapes: First evidence on contribution to the phenolics-oriented response
Lei WangZisheng LuoMingyi YangDong LiMing QiYanqun XuAsem Mahmoud AbdelshafyZhaojun BanFengzhong WangLi Li
67
Citation
39
Reference
10
Related Paper
Citation Trend
Keywords:
Phenylalanine ammonia-lyase
Cite
Citations (14)
Abstract The phosphonic analogue of ʟ-phenylalanine, (R)-(1-amino-2-phenylethyl)phosphonic acid (APEP), inhibits buckwheat phenylalanine ammonia-lyase (PAL) competitively with a K i value of 1.5 μM. The K i value for the (S)-enantiomer is 11.6 μM. The corresponding values for the enantiomers of the phosphonous analogue are 35 and 205 μm , respectively. APEP inhibits the light-induced synthesis of anthocyanin in hypocotyls of etiolated buckwheat seedlings and causes a specific increase in the endogenous phenylalanine concentration in buckwheat hypocotyls as well as other plant tissues. Kohlrabi seedlings develop normally in the presence of APEP, while their anthocyanin content is greatly reduced. These results indicate that APEP inhibits PAL in vivo.
Phenylalanine ammonia-lyase
Cite
Citations (36)
Phenylalanine ammonia-lyase
Cite
Citations (0)
Kinetic studies of the transport of aromatic amino acids by Pseudomonas aeruginosa revealed the existence of two high-affinity transport systems which recognized the three aromatic amino acids. From competition data and studies on the exchange of preformed aromatic amino acid pools, the first transport system was found to be functional with phenylalanine, tyrosine, and tryptophan (in order of decreasing activity), whereas the second system was active with tryptophan, phenylalanine, and tyrosine. The two systems also transported a number of aromatic amino acid analogues but not other amino acids. Mutants defective in each of the two and in both transport systems were isolated and described. When the amino acids were added at low external concentrations to cells growing logarithmically in glucose minimal medium, the tryptophan pool very quickly became saturated. Under identical conditions, phenylalanine and tyrosine each accumulated in the intracellular pool of P. aeruginosa at a concentration which was 10 times greater than that of tryptophan.
Cite
Citations (32)
Phenylalanine ammonia-lyase
Amino acid metabolism
Lyase
Cite
Citations (1)
Radioactivity from L-phenylalanine-carboxyl- 14 C was incorporated specifically into the carboxyl group of cinnamamide by cultures of Streptomyces verticillatus. L-Phenylalanine ammonia-lyase (EC. 4.3.1.5) could be extracted from the mycelium. Cultures grown in defined medium produced little cinnamamide unless supplemented with L-phenylalanine; phenylalanine ammonia-lyase activity in the mycelium was directly related to the yield of cinnamamide.
Phenylalanine ammonia-lyase
Lyase
Cite
Citations (47)
The conversion of trans-cinnamic acid to phenylalanine using phenylalanine ammonia lyase (PAL) was examined. The optimum concentration of trans-cinnamic acid for the reaction was observed at 100 mM in cells and at 20 mM in cell free extracts, respectively. The production of L-phenylalanine was increased in both experiments as the concentration of ammonia was increased up to 10 M. The optimal pHs for the maximal conversion of trans-cinnamic acid to L-phenylalanine were 9.5 and 9.0 in experiments carried out with cells and with cell free extracts, respectively.
Phenylalanine ammonia-lyase
Cinnamic acid
Cite
Citations (0)
L-phenylalanine is an important amino acid in commercial production of food industry and medicine nowaday. The biotransformations of trans-cinnamic acid to L-phenylalanine using phenylalanine ammonia- lyase(PAL) is in the front of research and development now.This article reviews the research progress in molecular biology of Phenylalanine ammonia-lyase (PAL) as an important enzyme for production of L-phenylalanine. Ref 43
Phenylalanine ammonia-lyase
Cinnamic acid
Lyase
Cite
Citations (0)
Abstract The ability of l ‐phenylalanine ammonia‐lyase (E.C. 4.3.1.5) to metabolize dl ‐ m ‐, dl ‐ o ‐ and dl ‐ p ‐fluorophenylalanine in Avena sativa has been examined. Although all three amino acid analogues served as substrates for this enzyme, there was a marked difference in the behavior of the meta isomer from that of the para and ortho species. The Michaelis constant for the meta analogue was similar to that obtained for the natural substrate, l ‐phenylalanine, but distinct from the kinetic data for the para and ortho isomers. In addition, in vivo analyses demonstrated that both l ‐phenylalanine and the meta‐fluoro‐derivative served to protect against chlorogenic acid loss, whereas previous studies have shown that the para and ortho species depressed levels of this phenolic derivative. Finally, treatment of coleoptile apices with either the meta isomer or l ‐phenylalanine reversed dl ‐ p ‐fluorophenylalanine stimulated growth and attendant reduction in chlorogenic acid content. These findings provide further clarification of the effects of fluorophenylalanines upon l ‐phenylalanine ammonia‐lyase mediated biosynthesis of low molecular weight phenols in Avena .
Phenylalanine ammonia-lyase
Avena
Phenylacetic acid
Chlorogenic Acid
Cite
Citations (2)