• Mycobiology
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• v.39 no.4
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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 The Korean Society of Inherited Metabolic disease
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• v.20 no.2
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• pp.37-43
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• 2020

Phenylketonuria is the most prevalent disorder caused by an inborn error in aminoacid metabolism. It results from mutations in the phenylalanine hydroxylase (PAH) gene. If untreated or late treated, results in profound and irreversible mental disability. Newborn screening test identify patients with phenylketouria. The early initiation of a phenylalanine restricted diet very soon prevents most of the neuropsychiatric complications. However, the diet therapy is difficult to maintain and compliance is poor, especially in adolescents and adulthood. Since 2015, American Medical College of Medical Genetics and Genomics (ACMG) recommended more strong restrictive diet therapy for target blood level of phenylalanine (<360 umol/L). For over four decades the only treatment was a very restrictive low phenylalanine diet. This changed in 2007 with the approval of cofactor therapy (Tetrahydrobiopterin, BH4) which is effective in up to 30% of patients. Data from controlled clinical trials with sapropterin dihydrochloride indicate a similar occurrence of all-cause adverse events with this treatment and placebo. Large neutral aminoacids (LNAA) competes with phenylalanine for transport across the blood-brain-barrier and have a beneficial effect on executive functioning. A new therapy has just been approved that can be effective in most patients with PAH deficiency regardless of their degree of enzyme deficiency or the severity of their phenotype. Phenylalanine ammonia lyase (PAL-PEG) was approved in the USA by FDA in May of 2018 for adult patients with uncontrolled blood phenylalanine concentrations on current treatment. Nucleic acid therapy (therapeutic mRNA or gene therapy) is likely to provide longer term solutions with few side effects.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.2
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• pp.158-161
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• 2003

Root cultures of Angelica gigas Nakai were found to be sensitive to elicitation by poly-saccharide elicitors, such as methyl-$\beta$-cyclodextrin, glucan, carboxymethyl-$\beta$-chitin, chitosan, yeast extract and pectin. For the production of decursinol angelate, ca rboxymethyl-$\beta$-chitin and glucan were found to be the most efficient elicitors. The e nhanced accumulation of decursinol angelate was proportional to the increase of the phenylalanine ammonialyase (PAL) activity after the treatment with most of the elicitors. However, carboxymethyl-$\beta$-chitin treatment did not stimulate the PAL activity, despite the 1.6-fold increase in the decursinol angelate production.

• Applied Biological Chemistry
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• v.14 no.1
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• pp.29-34
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• 1971

Changes in hot-taste component during the after-ripening period of hot pepper fruit were surveyed and summarized as follows; (1) Capsaicinoid contents were steadily increased as the after-ripening proceeded when physiological activity of the sample was suppressed during each stage of the ripening with the vacuum dry freezing. (2) It was assumed by determining phenylalanine contents and activities of phenylalanine ammonialyase to see synthetical process of capsaicin in the metabolic part of vanillylamine that there is a gradual synthesis and accumulation of capsaicin during the after-ripening period. (3) Lignin-like substances, as in the case of capsaicinoid, showed a steady increase during the after-ripening period. (4) The contents of polyphenolic compounds and polyphenol oxidase activity were higher with low temperature treatment.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.173.1-173
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• 2003

열처리는 과일의 저장성을 증가시키기 위하여 최근에 많이 사용되고 있다. 본 연구에서는 열처리가 사과의 내부 성분변화에 미치는 영향에 대하여 알아보았다. 45$^{\circ}C$에서 30분 동안 침지하여 열처리하였으며 풍건 후 4$^{\circ}C$에서 보관하면서 사과 내부의 일부 기능성 성분의 변화를 조사한 결과 total phenolic compound는 열처리 후 저장 5일째까지 증가하다가 감소하는 경향을 나타내었으며, 열처리구가 무처리구보다 지속적으로 증가하는 경향을 나타내었다. 항산화 활성은 열처리구의 경우 항산화 활성이 증가하였다. 감소하는 경향을 보였으며 무처리구는 지속적으로 증가하였다. Angiotensin converting enzyme (ACE) 활성은 열처리구 사과에서 저장 7일째까지 활성이 증가하다가 이후 감소하는 경향은 보인 반면 무처리구의 경우 저장 5일째까지 활성이 증가하다가 감소하는 경향을 나타내었으며 열처리한 사과가 ACE 저해 활성이 더 높게 나타났다. 아질산염 소거능은 무처리구가 열처리구보다 더 높은 효과를 나타내었고, 열처리 후 산도 및 환원당의 변화를 조사한 결과 무처리구가 열처리구보다 변화가 적게 나타났다. 또한 일반적으로 식물체가 stress를 받았을 때 phenylalanine ammonialyase (PAL) activity가 증가하므로 활성을 조사한 결과 무처리구에서 PAL activity의 급격한 증가가 나타났으며 열처리구에서 거의 증가하지 않았는데 이는 열처리에 의해 PAL를 포함한 단백질합성이 억제를 받아서 일 것으로 사료된다.

• Journal of Plant Biotechnology
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• v.31 no.3
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• pp.239-248
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• 2004

This experiment was carried out to confirm that phytochrome regulates anthocyanin bio-synthesis during cell suspension culture system of grape or not. In suspension culture of grape, maximum accumulation of anthocyanin was observed at the stationary phase under continuous white light condition. From mono-chromatic light interruption for 24h at the 4th or 7th day on the suspension cultured cells, the anthocyanin accumulation was highly enhanced at the light interruption at 7th day than 4th day under all monochromatic light treatment. However, the cell growth patterns were not affected by any light treatment. In the darkness, the anthocyanin synthesis was very low but remarkably increased by blue light or red light irradiation. However, the increase of anthocyanin accumulation by blue or red light was suppressed by far-red light in the suspension cells of grape. This suppression by far-red light on the anthocyanin synthesis also observed on the cells treated red or far-red light alternatively. These results implied that phytochrome regulation system may be involved in the anthocyanin biosynthesis of the suspension grape cells. By RNA expression analysis, chalcone synthase (CHS) gene was expressed highly by blue and red light but low by far-red light. The synergistic increase of CHS gene expression was also observed at the treatment of blue light followed by red for 24h. This result may explain the increase of anthocyanin accumulation in B/R treatment. Although the expression of phytochrome gene (PHYA or PHYB) was not highly increased by all light treatment (blue, red, and far-red light) the expression of both PHYA gene and PHYB gene was increased a little in cells treated red or far-red light. In grape suspension cells, the red light enhanced the anthocyanin synthesis, whereas the far-red light was suppressed. Although it was not confirmed whether or not phytochrome gene is activated in anthocyanin accumulating grape cells, we believed that anthocyanin biosynthesis in grape cells may be regulated under phytochrome signal transduction system.