• Journal of Microbiology and Biotechnology
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• 제30권4호
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• pp.622-632
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• 2020

Phenylalanine ammonia-lyase (PAL) catalyzes the reversible deamination of phenylalanine to cinnamic acid and ammonia. Algae have been considered as biofactories for PAL production, however, biochemical characterization of PAL and its potency for myristicin biotransformation into MMDA (3-methoxy-4, 5-methylenedioxyamphetamine) has not been studied yet. Thus, PAL from Anabaena flos-aquae and Spirulina platensis has been purified, comparatively characterized and its affinity to transform myristicin was assessed. The specific activity of purified PAL from S. platensis (73.9 μmol/mg/min) and A. flos-aquae (30.5 μmol/mg/min) was increased by about 2.9 and 2.4 folds by gel-filtration comparing to their corresponding crude enzymes. Under denaturing-PAGE, a single proteineous band with a molecular mass of 64 kDa appeared for A. flos-aquae and S. platensis PAL. The biochemical properties of the purified PAL from both algal isolates were determined comparatively. The optimum temperature of S. platensis and A. flos-aquae PAL for forward or reverse activity was reported at 30℃, while the optimum pH for PAL enzyme isolated from A. flos-aquae was 8.9 for forward and reverse activities, and S. platensis PAL had maximum activities at pH 8.9 and 8 for forward and reverse reactions, respectively. Luckily, the purified PALs have the affinity to hydroaminate the myristicin to MMDA successfully in one step. Furthermore, a successful method for synthesis of MMDA from myristicin in two steps was also established. Gas chromatography-mass spectrometry (GC-MS) analysis was conducted to track the product formation.

• Mycobiology
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• 제43권3호
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• pp.327-332
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• 2015

Phenylalanine ammonia-lyase (PAL) gene is known to be expressed in plants, and is involved in the differentiation, growth and synthesis of secondary metabolites. However, its expression in fungi remains to be explored. To understand its expression in mushroom fungi, the PAL gene of the edible mushroom Flammulina velutipes (Fvpal) was cloned and characterized. The cloned Fvpal consists of 2,175 bp, coding for a polypeptide containing 724 amino acids and having 11 introns. The translated amino acid sequence of Fvpal shares a high identity (66%) with that of ectomycorrhizal fungus Tricholoma matsutake. Distinctively, the Fvpal expression in the mycelium was higher in minimal medium supplemented with L-tyrosine than with other aromatic amino acids. During cultivation of the mushroom on sawdust medium, Fvpal expression in the fruit body correspondingly increased as the mushroom grew. In the fruiting body, Fvpal was expressed more in the stipe than in the pileus. These results suggest that F. velutipes PAL activity differs in the different organs of the mushroom. Overall, this is first report to show that the PAL gene expression is associated with mushroom growth in fungi.

• Archives of Pharmacal Research
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• 제19권3호
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• pp.219-222
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• 1996

Ephedra olistachya cultures have been known to accumulate $rho-coumaroylamino$ acids by elicitor treatment. Based on their chemical structures, the biosynthetic pathway of$rho-coumaroylamino$acids was postulated and phenylalanine ammonia-lyase (PAL), cinnamic acid 4-hydroxylase (4-CH) and p-coumaroyl CoA: D-Ala p-coumaroyltransferase ($rho-CT$) were supposed to be involved in the pathway. The time course inductions of these enzymes were investigated after treatment of yeast extract, yeast-derived mannan glycopeptide and D-Ala. They were detectable at only 4 hours and reached to their maximum level at 9 hours after onset of elicitor treatment. The activities of PAL and 4-CH were almost disappeared within 24 hours, however, that of $rho-CT$was remained up to 48 hours irrespective of the kind of elicitors. $rho-CT$ showed substrate specificity to D-Ala at crude enzyme extract level.

• BMB Reports
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• 제31권1호
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• pp.31-36
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• 1998

Phenylalanine ammonia-lyase (PAL; EC 4.3.1.5), the first enzyme in the phenylpropanoid biosynthesis, catalyzes the elimination reaction of ammonium ion from L-phenylalanine. PAL was purified from the cytosolic fraction of Chinese cabbage (Brassica campestris ssp. napus var. pekinensis) through ammonium sulfate fractionation, DEAE-cellulose chromatography, Sephadex G-200 chromatography, and Q-Sepharose chromatography. It consists of four identical subunits, the molecular mass of which was estimated to be about 38,000 daltons on SDS-PAGE. The optimal pH and temperature of the purified enzyme are 8~9 and $45^{\circ}C$, respectively. Its activity is greatly inhibited by $Zn^{2+}$ ion, and strongly activated by caffeic acid. The purified PAL has some different characteristics compared to those obtained with other PALs.

• Journal of Plant Biology
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• 제37권3호
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• pp.263-269
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• 1994

Involvement of ethylene and Ca2+ on the induction of phenylalanine ammonia-lyase (PAL) was investigated in Daucus carota L. suspension culture system. Ethylene production started to increase about 3 h after glucan treatment. And the maximal induction of ethylene was preceded by PAL induction by 30 min. After the treatment of ethrel, PAL activity was increased. When cells were treated with glucan and Co2+, PAL activity was simultaneously reduced. Ethylene production was reduced dramatically in calcium-free medium, even though glucan was treated. PAL activity and ethylene producton was inhibited conspicuously when ethylene glycolbis($\beta$-aminoethyl ether) N,N,N',N'-tetraacetic acid (EGTA) was treated with glucan. Verapamil and trifluoperazine also inhibited PAL activity. When cells were treated with calcium ionophore A23187, PAL activity was increased in nontreated medium. We report here PAl activity is increased in related to ethylene production and involvement of Ca2+ in glucan-treated carrot suspension cells.

• Mycobiology
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• 제39권4호
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• pp.257-265
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• 2011

L-Phenylalanine is one of the essential amino acids that cannot be synthesized in mammals in adequate amounts to meet the requirements for protein synthesis. Fungi and plants are able to synthesize phenylalanine via the shikimic acid pathway. L-Phenylalanine, derived from the shikimic acid pathway, is used directly for protein synthesis in plants or metabolized through the phenylpropanoid pathway. This phenylpropanoid metabolism leads to the biosynthesis of a wide array of phenylpropanoid secondary products. The first step in this metabolic sequence involves the action of phenylalanine ammonialyase (PAL). The discovery of PAL enzyme in fungi and the detection of $^{14}CO_2$ production from $^{14}C$-ring-labeled phenylalanine and cinnamic acid demonstrated that certain fungi can degrade phenylalanine by a pathway involving an initial deamination to cinnamic acid, as happens in plants. In this review, we provide background information on PAL and a recent update on the presence of PAL genes in fungi.

• Journal of Plant Biotechnology
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• 제6권3호
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• pp.151-156
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• 2004

Soil-borne fungal pathogens such as Verticillium and Rhizoctonia can colonize in the stem tissue of plant through root and lead to wilting symptoms of plant by blocking. water transportation. During the colonization of Rhizoctonia solani in the vascular tissue of tomato stems, particularly, phenylalanine ammonia-lyase (PAL) gene induction pattern was cyclized showing peak induction at two different time points (10 and 80 h) after fungal spores inoculation in vivo. In leaves or roots, however, no such cycling pattern was observed. The first induction peak may be due to an initial sporulation events leading to a second induction peak by a proliferation of fungal spores to the upper stems or other tissues from an initial spore trapping sites. Tomato PAL gene was also dramatically induced by wounding, light illumination and mercury chloride treatment but was not cyclized. Mercury chloride showed the earliest induction with all tissues even at half an hour after treatment.

• Bulletin of the Korean Chemical Society
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• 제15권5호
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• pp.387-390
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• 1994

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.

• Plant Biotechnology Reports
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• 제5권4호
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• pp.301-308
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• 2011

This study tested the relative and combined efficacy of ShPx2 and ShPAL transgenes by comparing Nicotiana tabacum hybrids with enhanced levels of $_L$-phenylalanine ammonia lyase (PAL) activity and cationic peroxidase (Prx) activity with transgenic parental lines that overexpress either transgene. The PAL/Prx hybrids expressed both transgenes driven by the 35S CaMV promoter, and leaf PAL and Prx enzyme activities were similar to those of the relevant transgenic parent and seven- to tenfold higher than nontransgenic controls. Lignin levels in the PAL/Prx hybrids were higher than the PAL parent and nontransgenic controls, but not significantly higher than the Prx parent. All transgenic plants showed increased resistance to the necrotrophs Phytophthora parasitica pv. nicotianae and Cercospora nicotianae compared to nontransgenic controls, with a preponderance of smaller lesion categories produced in Prx-expressing lines. However, the PAL/Prx hybrids showed no significant increase in resistance to either pathogen relative to the Prx parental line. These data indicate that, in tobacco, the PAL and Prx transgenes do not act additively in disease resistance. Stacking with Prx did not prevent a visible growth inhibition from PAL overexpression. Practical use of ShPAL will likely require more sophisticated developmental control, and we conclude that ShPx2 is a preferred candidate for development as a resistance transgene.

• BMB Reports
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• 제32권2호
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• pp.203-209
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• 1999

Three-week grown Arabidopsis thaliana leaves were wounded by cutting whole leaves with a razor blade into pieces (about$3\;mm\;{\times}\;3\;mm$) submerged in various solutions, and incubated in a growth chamber for 24 h. We measured and compared activities of several enzymes such as phenylalanine ammonia-lyase (PAL), tyrosine ammonia-lyase (TAL), thioredoxin, thioredoxin reductase, thioltransferase, glutathione reductase, and $NADP^+$ -malate dehydrogenase. PAL activity was decreased in $HgCl_2$-, $CdCl_2$-, and glyphosate-treated leaf slices, and could not be detected after treatment with $CdCl_2$. TAL activity was found to be maximal in the $CdCl_2$-treated leaf slices. Activity of thioredoxin, a small protein known as a cofactor of ribonucleotide reductase and a regulator of photosynthesis, was significantly increased in the $CdCl_2$-treated leaf slices, while thioredoxin reductase activity was maximal in the $HgCl_2$-treated leaf slices. Thioltransferase and glutathione reductase activities were significantly decreased in the $HgCl_2$-treated leaf slices. $NADP^+$ -malate dehydrogenase activity remained relatively constant after the chemical treatments. Our results strongly indicate that sulfhydryl-related and phenylpropanoid-synthesizing enzyme activities are affected by chemical treatments such as hydrogen peroxide, heavy metals, and glyphosate.