Phenylpropanoids, biosynthesis

WISMAN, E., HARTMANN, U., SAGASSER, M., BAUMANN, E., PALME, K., HAHLBROCK, K., SAEDLER, H., WEISSHAAR, B., Knock-out mutants from an En-1 mutagenized Arabidopsis thaliana population generate phenylpropanoid biosynthesis phenotypes, Proc. Natl. Acad. Sci. USA, 1998,95,12432-12437. 

BOREVITZ, J.O., XIA, Y, BLOUNT, J DIXON, R.A., LAMB, C., Activation tagging identifies a conserved MYB regulator of phenylpropanoid biosynthesis, Plant Cell,... 

FRICK, S., KUTCHAN, T.M., Molecular cloning and functional expression of O-methyltransferases common to isoquinoline alkaloid and phenylpropanoid biosynthesis, Plant J., 1999,17, 329-339. 

Results of Wulf et al (7) show that carrot roots obtained from a supermarket contain myristicin Imperator variety carrots contain an average of 15 parts per million (ppm). Recently harvested, unprocessed carrots only rarely contain myristicin (8). The presence of myristicin in supermarket carrots and its absence in recently harvested ones indicate that its increased concentration may have been induced by some elicitor following harvest. Solar radiation after harvest, or fluorescent lighting during display, may function as such an elicitor. Light is known to produce ethylene and is an activator of phenylalanine ammonia-lyase, one of the regulatory enzymes responsible for phenylpropanoid biosynthesis in plants (9). 

Enzymatic preparations for PAL from monocotyledonous species (monocots) can show a similar activity against tyrosine (tyrosine ammonia lyase, TAL), and TAL enzymatic preparations also show PAL activity. That a single enzyme may account for the observed cooccurring TAL and PAL activities was confirmed by Rosier et al., who showed the recombinant Zea mays (maize) PAL converted tyrosine to 4-coumarate directly, thus removing the requirement for the usual 4-hydroxylation step in phenylpropanoid biosynthesis. 

Flavanones are converted stereospecifically to the respective (2i ,3i )-dihydroflavonols (DHFs) by flavanone 3(3-hydroxylase. Stereospecificity for (2S)-flavanones has been confirmed by analysis of the recombinant protein. Flavanone 3(3-hydroxylase is commonly abbreviated to F3H, which is what has been used in this chapter, but FHT is also used in the literature, which agrees with the nomenclature for phenylpropanoid biosynthesis proposed in Heller and Forkmann. ... 

Szalma, S.J. et al., Duplicate loci as QTL the role of chalcone synthase loci in flavone and phenylpropanoid biosynthesis in maize, Crop ScL, 42, 1679, 2002. 

Phenylpropanoid biosynthesis gives rise to caffeic acid, lignins,... 

Hoffmann, L., Besseau, S., Geoffroy, P., Ritzenthaler, Ch., Meyer, D., Lapierre, C., Pollet, B., and Legrand, M., 2004, Silencing of hydroxycinnamoyl-coenzyme A shikimate/quinate hydroxyltransferase affects phenylpropanoid biosynthesis, Plant Cell 16 1446-1465. 

Phenylpropanoid Biosynthesis in Plants Enzymology and Pathway Topology 491 Transcriptional and Posttranscriptional Regulation of Phenylpropanoid Biosynthesis in Plants 504... 

Phenylpropanoid Biosynthesis in Plants Enzymology and Pathway Topology... 

Transcriptional and Posttranscriptional Regulation of Phenylpropanoid Biosynthesis in Plants... 

Table 21.1 Plant Transcription Factors Involved in Phenylpropanoid Biosynthesis Regulation and Their Known Regulons...

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. 

Mehrtens F, Kranz H, Bednarek P, Weissaar B. 2005. The Arabidopsis thaliana transcription factor MYB12 is a flavonol-specific regulator of phenylpropanoid biosynthesis. Plant Physiol 138 1083-1096. 

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