Phenylketonuria (PKU), with its associated hyperphenylalaninemia (HPA) and mental retardation, is a classic genetic disease and the first to have an identified chemical cause of impaired cognitive development. Treatment from birth with a low phenylalanine diet largely prevents the deviant cognitive phenotype by ameliorating HPA and is recognized as one of the first effective treatments of a gen...

Pharmacological evidence implicates trans-cinnamic acid as a feedback modulator of the expression and enzymatic activity of the first enzyme in the phenylpropanoid pathway, L-phenylalanine ammonia-lyase (PAL). To test this hypothesis independently of methods that utilize potentially non-specific inhibitors, we generated transgenic tobacco lines with altered activity levels of the second enzyme ...

A separable and highly-stable enzyme system was developed by adsorption of phenylalanine ammonia lyase (PAL) from Rhodotorula glutinis in amino-functionalized macroporous silica gel and subsequent enzyme crosslinking. This resulted in the formation of cross-linked enzyme aggregates (PAL-CLEAs) into macroporous silica gel (MSG-CLEAs). The effect of adsorptive conditions, type of aggregating agen...

Species-specific changes in expression of phenylalanine ammonia-lyase (PAL) and lignin content were detected in roots of soybean (Glycine max L.) and lupine (Lupinus luteus L.) seedlings treated with different concentrations of cadmium (Cd(2+), 0-25 mg/l) or lead (Pb(2+), 0-350 mg/l). The stimulatory effect of both metals was observed in mRNA coding for PAL in soybean. In the case of lupine, ch...

PAL (L-phenylalanine ammonia-lyase), the first enzyme of phenylpropanoid biosynthesis, is often encoded by multigene families in plants. A PCR-based approach was used to isolate cDNA clones corresponding to the four PAL genes of tobacco (Nicotiana tabacum). By careful comparison of cDNA and genomic clones, a new PAL gene (PAL4) was defined. PCR amplification of PAL sequences from cDNA led to th...

The oscillations in phenylalanine aunnnia-lyase activity from Spirodels pelyrhiza and phenylalanine ammonia-lyase and tyrosine ammonia-lyase activities from Lemnas perpusilam disayed a circadian rhythm under continuous lght. Rhythmiclty in enzymic activity could not be detected in continuous darkness since under this condition phenylalanine ammonialyase activity remains at a fairly constantly l...

Metabolic channeling has been proposed to occur at the entry point into plant phenylpropanoid biosynthesis. To determine whether isoforms of L-Phe ammonia-lyase (PAL), the first enzyme in the pathway, can associate with the next enzyme, the endomembrane-bound cinnamate 4-hydroxylase (C4H), to facilitate channeling, we generated transgenic tobacco (Nicotiana tabacum) plants independently express...

In the present study, Phenylalanine ammonia lyase (PAL) activity was detected in different parts of grape plant (leaves, pulp, whole seeds and defatted seeds) extracts. The results revealed that seed possess highest PAL (69.44 U), followed by (44.22 whereas extracts leaves pulp gave lowest values (22.77 5.11 U, respectively). optimum conditions for crude extraction achieved using 50mM potassium...

In this study, a phenylalanine ammonia-lyase (PAL) gene was cloned from Dendrobium candidum using homology cloning and RACE. The full-length sequence and catalytic active sites that appear in PAL proteins of Arabidopsis thaliana and Nicotiana tabacum are also found: PAL cDNA of D. candidum (designated Dc-PAL1, GenBank No. JQ765748) has 2,458 bps and contains a complete open reading frame (ORF) ...

Phenylalanine ammonia-lyase (PAL) is the first enzyme involved in the phenylpropanoid pathway and plays important roles in the secondary metabolisms, development and defense of plants. To study the molecular function of PAL in anthocyanin synthesis of Coleus (Solenostemon scutellarioides (L.) Codd), a Coleus PAL gene designated as SsPAL1 was cloned and characterized using a degenerate oligonucl...