Cinnamic

Other experiments with Gibberellafujikuroi the fungus that produces gibbereUin, indicate that GA production is blocked by BAS 111. Very detailed and carehil experiments conducted with enzymes in ceU-free systems strongly support this mode of action, ie, using /-kaurene oxidase and cinnamate 4-mono-oxygenase isolated from pea apices and soybean suspension cells, and avanone-2-hydtoxylase and dibydroxypterocarpane 6-hydtoxylase from soybean suspension cells (31). 

Figure 5.4. Abbreviated scheme for biosynthesis of major flavonoid subclasses, showing the primary enzymes and substrates leading to different subclasses. Bold-faced, uppercase abbreviations refer to enzyme names, whereas substrate names are presented in lowercase letters. PAL, phenylalanine ammonia lyase C4H, cinnamate 4-hydroxylase 4CL, 4-coumarate CoA ligase CHS, chalcone synthase CHI, chalcone isomerase CHR, chalcone reductase IPS, isoflavone synthase F3H, flavonone 3-hydroxylase F3 H, flavonoid 3 -hydroxylase F3 5 H, flavonoid 3 5 -hydroxylase FNSI/II, flavone synthase DFR, dihydroflavonol 4-reductase FLS, flavonol synthase ANS, anthocyanidin synthase LAR, leucoanthocyanidin reductase ANR, anthocyanidin reductase UFGT, UDP-glucose flavonoid 3-O-glucosyltransferase. R3 = H or OH. R5 = H or OH. Glc = glucose. Please refer to text for more information.

Figure 6.1 Major branch pathways of flavonoid biosynthesis in Arabidopsis. Branch pathways, enzymes, and end products present in other plants but not Arabidopsis are shown in light gray. Abbreviations cinnamate-4-hydroxylase (C4H), chalcone isomerase (CHI), chalcone synthase (CHS), 4-coumarate CoA-ligase (4CL), dihydroflavonol 4-reductase (DFR), flavanone 3-hydroxylase (F3H), flavonoid 3 or 3 5 hydroxylase (F3 H, F3 5 H), leucoanthocyanidin dioxygenase (LDOX), leucoanthocyanidin reductase (LCR), O-methyltransferase (OMT), phenylalanine ammonia-lyase (PAL), rhamnosyl transferase (RT), and UDP flavonoid glucosyl transferase (UFGT).

TEUTSCH, H.G., HASENFRATZ, M.P., LESOT, A., STOLTZ, C., GARNIER, J.M., JELTSCH, J.M., DURST, F., WERCK-REICHHART, D., Isolation and sequence of a cDNA encoding the Jerusalem artichoke cinnamate 4-hydroxylase, a major plant cytochrome P450 involved in the general phenylpropanoid pathway, Proc. Natl. Acad. Sci. USA, 1993,90,4102-4106. 

A 100 mL flask, was filled with (Z)-ethyl cinnamate, (666 mg of the mixture containing 75 % of (Z)-ethyl cinnamate), 4-phenylpyridine N-oxide (116 mg) and dichloromethane (6mL). Jacobsen s catalyst (108 mg) was then added. 

Cinnamate 4-hydroxylase (C4H EC 1.14.13.11, also defined as CYP73A [36]) catalyzes the p-hydroxylation of trani-cinnamate to form trani -p-coumarate. The enzyme has a requirement for molecular oxygen and NADPH as well as association with the electron donor NADPH-cytochrome P450 reductase (CPR EC 1.6.2.4) for activity. C4H was the first characterized plant P450 [37, 38]. 

RusseU DW, Conn EE (1967) The cinnamic 4-hydroxylase of pea seedlings. Arch Biochem Biophys 122 256-258... 

RusseU D (1971) The metabolism of aromatic compounds in higher plants X. Properties of the cinnamic 4-hydroxylase of pea seedlings and some aspects of its metabolic and experimental control. J Biol Chem 246(12) 3870-3878... 

Ro DK, Mah N, EUis BE, Douglas CJ (2001) Functional characterization and subcellular localization of poplar (Populus trichocarpa x Populus deltoides) cinnamate 4-hydroxylase. Plant Physiol 126(1) 317-329... 

Betz C, McCollum TG, Mayer RT (2001) Differential expression of two cinnamate 4-hydroxylase genes in Valencia orange (Citrus sinensis Osbeck) Plant Mol Biol 46(6) 741-748... 

This enzyme [EC 1.14.13.11], also known as cinnamate 4-hydroxylase, catalyzes the reaction of frans-cinnamate with NADPH and dioxygen to generate 4-hydroxycmna-mate, NADP+, and water. The enzyme, which uses a heme-thiolate as a cofactor, can also replace NADPH with NADH (however, the reaction will proceed slower). 

PHENYLALANINE AMMONIA-LYASE trans-CINNAMATE 4-MONOOXYGENASE CIRGADIAN RHYTHM CIRGE EFFEGT... 

The chemical and physical evidence for the presence of lignin in the material deposited at wound margins is supported by biochemical studies on the enzymes involved in phenylpropanoid metabolism. Thus, the extractable activities of phenylalanine ammonia-lyase, tyrosine ammonia-lyase, cinnamate-4-hydroxylase, caffeic acid O-methyltransferase,... 

Coumaroyl-CoA is produced from the amino acid phenylalanine by what has been termed the general phenylpropanoid pathway, through three enzymatic conversions catalyzed by phenylalanine ammonia-lyase (PAL), cinnamate 4-hydroxylase (C4H), and 4-coumarate CoA ligase (4CL). Malonyl-CoA is formed from acetyl-CoA by acetyl-CoA carboxylase (ACC) (Figure 3.2). Acetyl-CoA may be produced in mitochondria, plastids, peroxisomes, and the cytosol by a variety of routes. It is the cytosolic acetyl-CoA that is used for flavonoid biosynthesis, and it is produced by the multiple subunit enzyme ATP-citrate lyase that converts citrate, ATP, and Co-A to acetyl-CoA, oxaloacetate, ADP, and inorganic phosphate. ... 

Hiibner, S. et al.. Functional expression of cinnamate 4-hydroxylase from Ammi majus L. Phytochemistry, 64, 445, 2003. 

Nedelkina, S. et al.. Novel characteristics and regulation of a divergent cinnamate 4-hydroxylase (CYP73A15) from French bean engineering expression in yeast. Plant Mol. Biol, 39, 1079, 1999. 

Koopmann, E., Logemann, E., and Hahlbrock, K., Regulation and functional expression of cinnamate 4-hydroxylase from parsley. Plant Physiol, 119, 49, 1999. 

Fig. (1). Schematic view of some branches of phenylpropanoid metabolism. Solid arrows indicate enzymatic reactions with the respective enzyme indicated on the right. PAL, phenylalanine ammonia-lyase C4H, cinnamate 4-hydroxylase 4CL, 4-coumarate CoA ligase CHS, chalcone synthase CF1, chalcone flavavone isomerase F3H, flavanone 3-hydroxylase DFR, dihydroflavonol reductase CHR, chalcone reductase. Broken arrows indicate metabolic branches towards several classes of phenylpropanoids, or several subsequent enzymatic steps. In some cases the enzymes indicated are also involved in other reactions, not shown.

Figure 1.35 Schematic diagram of the phenolic biosynthetic pathway accompanied by the key enzymes involved. Enzyme abbreviations PAL, phenylalanine ammonia-lyase BA2H, benzoic acid 2-hydroxylase C4H, cinnamate 4-hydroxylase COMT-1, caffeic/5-hydroxyferulic acid O-methy I transferase 4CL, p-co um a ra te C o A ligase F5H, ferulate 5-hydroxylase GT, galloyltransferase ACoAC, acetylCoA carboxylase.

Achnine L, Blancaflor EB, Rasmussen S, Dixon RA. 2004. Colocalization of L-phenylalanine ammonia-lyase and cinnamate 4-hydroxylase for metabolic channeling in phenylpropanoid biosynthesis. Plant Cell 16 3098-3109. 

Fig. 1. Simplified diagram of the phenylpropanoid and flavonoid biosynthetic pathways. Enzymes that catalyze the reactions are placed on the left-hand side, and transcription factors on the right-hand side of the arrows. Both transcription factors for which their control over the enzymatic steps has been genetically proven, as well as transcription factors that have been shown to interact with promoters of the structural genes, are shown. PAL Phenylalanine ammonia lyase C4H cinnamate 4-hydroxylase 4CL 4-coumaroyl-coenzyme A ligase CHS chalcone synthase CHI chalcone-flavanone isomerase F3H flavanone 3(3-hydroxylase DFR dihydroflavonol 4-reductase AS anthocyanin synthase UFGT UDP glucose-flavonol glucosyl transferase RT anthocyanin rhamnosyl transferase...

Batard, Y., Schalk, M., Pierrel, M.-A., Zimmerlin, A., Durst, F., and Werck-Reichhart, D., Regulation of the cinnamate 4-hydroxylase (CYP73A1) in Jerusalem artichoke tubers in response to wounding and chemical treatments, Plant Physiol., 113, 951-959, 1997. 

Kochs, G., Werck-Reichhart, D., and Grisebach, H., Further characterization of cytochrome P450 involved in phytoalexin synthesis in soybean cytochrome P450 cinnamate 4-hydroxylase and 3,9-dihydroxyptero-carpan 6a-hydroxylase, Arch. Biochem. Biophys., 293, 187-194, 1992. 

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