• The Plant Pathology Journal
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• 제35권5호
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• pp.406-416
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• 2019

Strawberry, an important fruit crop, is susceptible to a large number of pathogens that reduce fruit quality and productivity. In this study, the effect of a biostimulant prepared from Ascophyllum nodosum extract (ANE) (0.1%, 0.2%, and 0.3%) was evaluated on powdery mildew progression under greenhouse and field conditions. In the greenhouse, application of 0.2% ANE showed maximum reduction in powdery mildew progression as compared to the control. Forty-eight hour post-inoculation, foliar spray of 0.2% ANE reduced spore germination by 75%. Strawberry leaves sprayed with ANE showed higher total phenolic and flavonoid content in response to powdery mildew infection. Furthermore, application of ANE elicited defense response in strawberry plants by induction of defense-related enzymes, such as phenylalanine ammonia lyase, polyphenol oxidase, and peroxidase activity. In field conditions, foliar spray of 0.2% ANE showed a reduction of 37.2% of natural incidence of powdery mildew infection as compared to the control. ANE sprayed plant also reduces the severity of powdery mildew infection under natural conditions. These results indicate that application of ANE induces the strawberry plant's active defense against powdery mildew infection by induction of secondary metabolism and regulating the activities of defense-related enzymes.

• Journal of Microbiology and Biotechnology
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• 제27권5호
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• pp.975-982
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• 2017

Curcumin, a hydrophobic polyphenol derived from the rhizome of the herb Curcuma longa, possesses diverse pharmacological properties, including anti-inflammatory, antioxidant, antiproliferative, and antiangiogenic activities. Two curcuminoids (dicinnamoylmethane and bisdemethoxycurcumin) were synthesized from glucose in Escherichia coli. PAL (phenylalanine ammonia lyase) or TAL (tyrosine ammonia lyase), along with Os4CL (p-coumaroyl-CoA ligase) and CUS (curcumin synthase) genes, were introduced into E. coli, and each strain produced dicinnamoylmethane or bisdemethoxycurcumin, respectively. In order to increase the production of curcuminoids in E. coli, the shikimic acid biosynthesis pathway, which increases the substrates for curcuminoid biosynthesis, was engineered. Using the engineered strains, the production of bisdemethoxycurcumin increased from 0.32 to 4.63 mg/l, and that of dicinnamoylmethane from 1.24 to 6.95 mg/l.

• EDISON SW 활용 경진대회 논문집
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• 제2회(2013년)
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• pp.203-204
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• 2013

Phenylalanine Ammonia Lyase (PAL)는 phenylalanine의 산성도가 더 큰 ammonium hydrogen 과는 반응하지 않고 그것의 nonacidic ${\beta}$ proton을 제거하는 역할을 한다. Phenylalanine은 electrophilic 그룹을 갖고 있으며 지난 30 여년 동안 phenylalanine의 electrophilic 그룹이 PAL의 반응 기작에 중요한 역할을 한다고 믿어왔다. 그러나 최근 X-ray와 UV spectroscopy를 통하여 상당히 electrophilic 한 5-methylene-3,5-dihydroimidazol-4-one (MIO) 그룹이 발견되었다. 이전의 연구들은 실험을 통하여 MIO와 관련된 electrophile에 의한 Friedel-Crafts Attack 메커니즘과 electrophile에 대한 nucleophilic addition 메커니즘을 제시하였으며, 본 연구진은 양자계산을 통하여 두 가지 메커니즘의 에너지 차이를 살펴봄으로써 더욱 합리적인 메커니즘을 제시, 규명하고자 한다. 본 연구에서는 특히 electrophile에 대한 nucleophilic addition 메커니즘에 대하여 양자계산을 이용하여 반응물, 생성물, 전이상태의 분자 구조를 제시하고 반응이 일어나는데 필요한 에너지를 계산하고자 한다.

• Journal of Microbiology and Biotechnology
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• 제20권3호
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• pp.622-629
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• 2010

Biosynthetic studies on brasiliamides, potently convulsive and bacteriostatic compounds from an endophytic Penicillium brasilianum isolated from Melia azedarach (Meliaceae), confirms their phenylpropanoid origin, which is very uncommon in fungi. Feeding experiments with [$2-^{13}C$]-phenylalanine indicated the incorporation of two units of this amino acid on brasiliamide structures. The first step in the phenylpropanoid pathway to those compounds was evaluated through enzymatic bioassays and confirmed the phenylalanine ammonia-lyase (PAL) participation. The metabolism of phenylalanine in this fungus is discussed.

• Journal of Plant Biotechnology
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• 제32권4호
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• pp.293-300
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• 2005

배추 유식물 제 1엽의 생장에 미치는 sodium nitroprusside(SNP: NO 공여체)의 생리적 효과를 NO에 의한 세포 분열조절의 가능성 수준에서 조사하였다. 배추 유식물에 서로 다른 농도의 SNP (0, 200, 500 및 $1000\;{\mu}M$)를 8일간 처리하고 배양한 결과 $200\;{\mu}M$ SNP 농도에서 최대 잎 생장을 보이면서 처리농도 의존 방식으로 잎의 생장에 영향을 끼쳤다. 잎의 생장반응과 일치하여, 잎의 엽록소 및 수용성 단백질 함량은 $200\;{\mu}M$농도에서 최대로 증가하여 각각 대조구의 142%와 134%수준을 보였으나, 오히려 $1000\;{\mu}M$처리농도에서는 엽록소의 경우 미미한 감소와 그리고 단백질 함량에서는 13%의 감소가 일어났다. 게다가, 잎 조직의 DNA와 RNA 함량 역시 $200\;{\mu}M$ 처리시 최대로 증가하여 각각 대조구의 142% 및 139% 수준을 보였으나, 반면에 $1000\;{\mu}M$ 농도에서는 각각 대조구의 80% 및 84% 수준까지 감소되었다. 세포벽 합성과 관련된 효소 활성도 변화에서 phenylalanine ammonia-lyase와 guaiacol peroxidase 활성도는 $200\;{\mu}M$ SNP 처리시 대조구에 비해 각각 최대 212%와 134% 증가 하였으나, $1000\;{\mu}M$ 농도에서는 두 효소 활성도 모두 유의한 변화를 보이지 않았다. 결론적으로, 이들 결과는 효과적인 농도에서의 SNP 처리에 의한 배추 제 1엽의 생장 촉진 현상은 세포분열 유도에 대한 NO의 능력에 기인될 수 있음을 제시하는 것이다.

• 식물조직배양학회지
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• 제26권1호
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• pp.41-47
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• 1999

토마토의 genomic DNA library로부터 분리한 tPALl, tPAL4유전자의 염기서열을 분석하여 tPAL5 유전자와 비교 분석한 결과는 다음과 같다. tPAL5 유전자는 722개의 아미노산과 710 bp의 intron을 가지고 있으나 tPALl은 intron을 가지고 있지 않으며 또한 tPAL5 유전자와 비교하여 249개의 짧은 polypeptide를 가지고 있었다. tPAL4유전자인 경우 357개의 아미노산과 305bp의 intron을 가지고 있었다. tPAL 효소간의 아미노산 homology는 tPAL1유전자와 tPAL4 유전자간은 87.2%, tPALl과 tPAL5는 85.3%, tPAL4 와 tPAL5 는 91.4%의 homology를 보였다. 또한, tPALl, tPAL4 유전자는 정상적인 polypeptide를 가지는 tPAL5유전자와 비교하여 비정상적인 stop codon을 가진 짧은 polypeptide로 구성되어 있었다. 다양한 식물 종으로부터 분리된 PAL유전자의 염기서열을 비교한 결과 토마토 (Lycopersicon esculentum), 감자 (Solanum tuberosum), 고구마 (Ipomoea batatas)간의 유연관계과 높았으며, parsley (Petroselinum crispum), bean (Phaseolus vulgaris), pea (Pisum sativum), alfalfa (Medicago sativa) 등이 각각 서로간에 유연관계가 높았다. 또한, 토마토에서 분리한 family내에서 tPAL4와 tPAL5 유전자는 homology가 매우 높았고 (93.0%), tPAL1와 tPAL4유전자 사이는 다소 낮았으며 (84.4%), 특히 tPAL4는 감자의 PAL 유전자와 매우 높았다 (90.6%).

• 생명과학회지
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• 제12권3호
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• pp.274-280
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• 2002

Phenylpropanoid pathway 생성물질은 식물의 self-defense에 관계하며 이러한 물질들은 UV뿐 아니라 wounding, pathogen과 같은 environmental stress에 의해 생성되는 것으로 알려져 있다. 벼에서 PAL mRNA 는 UV 조사 후 12시간에서 48시간까지는 증가하였으나 48시간부터 60시간까지는 점점 줄어드는 경향을 보였다. 한편 PAL의 활성은 UV조사 후 24시간에서 가장 높았지만 상처에 의해서는 PAL의 활성이 벼에서는 증가하지 않았다. 그러나 고추에서는 UV조사와 상처를 준 후 24시간과 10시간에서 각각 높은 활성을 나타내었다. 벼와 고추 모두 cinnamic acid 4-hydroxylase의 활성은 상처를 준 후 12시간에서 증가하였지만 UV 조사는 C4H 활성에 영향을 주지 않았다. 이러한 결과로 볼 때 벼와 고추에서는 UV 조사와 상처가 모두 PAL, C4H 효소활성에 영향을 주는 것으로 나타났다.

• 원예과학기술지
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• 제30권1호
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• pp.6-12
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• 2012

Early growth, pigmentation, protein content, and phenylalanine ammonia-lyase (PAL) activity of red curly lettuces (Lactuca sativa L.) grown under different lighting conditions were investigated. Fluorescent lamps (control), blue, red, and blue plus red light-emitting diodes (LEDs) were used as light sources for 10 days. An equal proportion (1:1) of blue and red LEDs was used in the mixed radiation condition. Compared with the control, monochromic red or blue lighting increased fresh and dry weights of 'Ttuksum' and 'Jaju' lettuces. Anthocyanin synthesis was also significantly promoted by the mixed radiation of blue and red LEDs. The mixed radiation also increased the protein content and PAL enzyme activity of 'Ttuksum' leaves by about 200% compared to other treatments. Anthocyanin content was the highest in lettuces subjected to the mixture radiation of blue and red light treatment, while anthocyanin synthesis was inhibited by monochromic red light. The results of the present study indicate that growth and pigment synthesis in lettuces are significantly enhanced by exposure to mixed radiation from blue and red LEDs.

• 한국초지조사료학회지
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• 제34권1호
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• pp.15-20
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• 2014

To investigate lignification process and its physiological significance under water-deficit condition, the responses of peroxidases, polyphenol oxidase (PPO) and phenylalanine ammonia-lyase (PAL) in relation to leaf water status to the short term of water deficit treatment in the leaves with different maturities in forage rape were measured. The significant decrease in relative water content (RWC) and leaf osmotic potential (${\Psi}{\pi}$) were apparent after 5 d of water-deficit treatment. The activity of guaiacol peroxidase (GPOD), ascorbate peroxidase (APOD), coniferyl alcohol peroxidase (CPOD), and syringaldazine peroxidase (SPOD) was depressed especially in middle and old leaves when compared with that of control leaves. On the other hand, in young leaves, a significant increase in CPOD (+34%) and SPOD (+24%) activity as affected by water-deficit treatment was apparent. The activation of PAL and PPO was observed in middle and old leaves for PAL and in young and middle leaves for PPO. These results suggest that peroxidases in middle and old leaves did not involve in lignification under mild water-deficit stress, whereas CPOD and SPOD in young leaves participate in lignification by a coordination with PAL and PPO to incorporate phenol and lignin into the cell walls.

• The Plant Pathology Journal
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• 제35권4호
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• pp.330-340
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• 2019

The present study was undertaken to evaluate the integrated effect of zinc (Zn) with other nutrients in managing early blight (EB) disease in tomato. A pot experiment was carried out with basal application of the recommended level of macronutrients [nitrogen, phosphorus and potassium (NPK)] and micronutrients [magnesium (Mg) and boron (B)] in bilateral combination with Zn (2.5 and 5.0 mg/kg) in a completely randomized deigned in replicates. Results revealed that interactive effect of Zn with Mg or B was often futile and in some cases synergistic. Zn with NPK yield synergistic outcome, therefore EB disease was managed significantly (disease incidence: 25% and percent severity index: 13%), which resulted in an efficient signaling network that reciprocally controls nutrient acquisition and uses with improved growth and development in a tomato plant. Thus, crosstalk and convergence of mechanisms in metabolic pathways resulted in induction of resistance in tomato plant against a pathogen which significantly improved photosynthetic pigment, total phenolics, total protein content and defense-related enzymes [superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), polyphenol oxidase (PPO) and phenylalanine ammonia-lyase (PAL)]. The tremendous increase in total phenolics and PAL activity suggesting their additive effect on salicylic acid which may help the plant to systemically induce resistance against pathogen attack. It was concluded that interactive effect of Zn (5.0 mg/kg) with NPK significantly managed EB disease and showed positive effect on growth, physiological and biochemical attributes therefor use of Zn + NPK is simple and credible efforts to combat Alternaria stress in tomato plants.