• The Korean Journal of Food And Nutrition
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• v.9 no.4
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• pp.430-433
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• 1996

The activity of PAL, an initial and key regulatory enzyme in biosynthesis of phenolics, peaked during ripening stage. The enzyme activities were 5.60 and 4.25 units/100g fr. wt. in ripening and overripening stages. The increase in PAL activity in ripening strawberry fruits is due to de novo synthesis of the enzyme. PAL extracts from ripe strawberry fruits have a native molecular weight of about 260, 000 Da.

• Journal of Microbiology and Biotechnology
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• v.30 no.4
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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.

• The Korean Journal of Mycology
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• v.39 no.3
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• pp.205-212
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• 2011

Phenylalanine ammonia-lyase (PAL) from the maize pathogen Ustilago maydis was analysed immunologically to obtain insights into the structural relationships between plant PAL and fungal PAL and between PAL and histidine ammonia-lyase (HAL). Cross-reactivity was found among all the PAL proteins from different species tested, using antibodies raised against both plant and fungal PALs. Both anti-Alfalfa and anti-popular PAL antibodies strongly recognized plant PALs but only weakly recognized fungal PALs. Antibodies raised against U. maydis PAL only weakly recognized the Rhodotorula glutinis yeast PAL. The anti-U. maydis PAL antibodies showed low affinity for the plant PALs but they bound strongly to Pseudomonas bacterial HAL. Significant cross-reactivity between the two plant PAL antibodies and the bacterial HAL was also observed. Both the anti-Ustilago PAL and the anti-poplar PAL antibodies displayed similar enzyme inhibition patterns, including moderate inhibition of bacterial HAL activity. However, the bacterial HAL antibody inhibited only Ustilago PAL. The PAL and HAL antibodies tested showed no inhibition against yeast PAL. This is first report on the immunological relationships between PAL and HAL.

• Journal of Nutrition and Health
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• v.56 no.4
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• pp.391-403
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• 2023

Purpose: This study evaluated the validity of a physical activity classification table (PACT) based on total energy expenditure (TEE) and physical activity level (PAL) measured using the doubly labeled water (DLW) method in Korean adults and the elderly. Methods: A total of 141 (male 70, female 71) adults and elderly were included. The reference standards TEE_DLW, PAL_DLW were measured over a 14-day period using DLW. A 24-hour physical activity diary was kept for three days (two days during the week and one day on the weekend). PAL_PACT was calculated by classifying the activity type and intensity using the PACT. PAL_PACT was multiplied by resting energy expenditure measured by indirect calorimetry to estimate TEE_PACT. Results: The mean age of the study participants was 50.5 ± 18.8 years, and the mean body mass index was 23.4 ± 3.3 kg/m². A comparison of TEE_DLW and TEE_PACT by sex and age showed no significant differences. The bias, the difference between TEE_DLW and TEE_PACT, was male 17.3 kcal/day and female -4.5 kcal/day. The percentage of accurate predictions (values within ± 10% of the TEE_DLW) of TEE_PACT was 58.6% in males and 54.9% in females, with the highest prediction values in the age group 40-64 years (70.9%) in males and over 65 years (73.9%) in females. The spearman correlation coefficient (r) between TEE_PACT and TEE_DLW was 0.769, indicating a significant positive correlation (p < 0.001). Conclusion: In this study, the use of a new PACT for calculating TEE and PAL was evaluated as valid. A web version of the software program and a smartphone application need to be developed using PACT to make it easier to apply for research purposes.

• Journal of Life Science
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• v.19 no.9
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• pp.1226-1231
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• 2009

Enzyme substitution with recombinant phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) is currently being explored for treatment of phenylketonuria (PKU), an autosomal recessive genetic disorder with mutations of the gene encoding phenylalanine-4-hydroxylase (EC 1.14.16.1). However, oral administration of PAL is limited because of proteolytic digestion in the gastrointestinal tract. The aim of this study was to determine the biochemical properties of PAL and delinate the susceptibility of wild-type PAL to pancreatic proteolysis by exploring several mutants, and to develop therapeutic drugs with PAL for PKU. The specific activity of PAL was assayed and its optimal pH, temperature stability, and intestinal protease susceptibility were investigated. Its $V_{max}$ values for phenylalanine and tyrosine were 1.77 and $0.47{\mu}mol$/ min/mg protein, respectively, and its $K_m$ values were $4.77{\times}10^{-4}$ and $4.37{\times}10^{-4}\;M$, respectively. PAL showed an optimal pH at 8.5, corresponding to the average pH range of the small intestine. It showed no loss of activity at $-80^{\circ}C$ for 5 months and possessed 93.4% of its activity under $4^{\circ}C$ for 4 wks. PAL was susceptible to chymotrypsin digestion and, to a lesser extent, to trypsin, elastase, carboxypeptidase A, and B. The trypsin and chymotrypsin cleaving sites were mutated to investigate protection from pancreatic digestion and the specific activities of these mutants were evaluated. The six mutants displayed low specific activities compared to the wild-type, suggesting that the primary trypsin and chymotrypsin cleaving sites may be essential for catalytic reaction. The PAL mutants could therefore be applied as a pretreatment modality without susceptibility to proteolytic attack, however, additional modification for enhancing enzymatic activity is needed to reduce the Phe levels effectively.

• Korean Journal of Plant Tissue Culture
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• v.25 no.2
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• pp.89-93
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• 1998

Tomato phenylalanine ammonia-lyase 5 (tPAL5) was identified that alternate initiation sites were utilized differentially in response to environmental stimuli (Lee et al, 1992b). In this study, we tried to look into tissue -or cell- specific expression pattern of tPAL5 gene by fusing with ${\beta}-glucuronidase$ (GUS) gene in transgenic tobacco plants. In transgenic plants, root and stem extracts contained 8~12 fold higher levels of GUS activity than petiole or leaf tissue while the highest levels of induction was observed from leaf tissue by mechanical wounding (5~11 fold). In trans-sections of stems and petioles, GUS activity was restricted to phloem cells(outer region) of developing vascular bundle and mainly at apical tip region in the root tissues. The levels of GUS activity was drastically reduced (10~12 fold reduction) when the 5'-upstream region of tPAL5 gene (-1151bp from ATG codon) was deleted up to -665. The levels of GUS expression, however, raised up by 6~8 fold when deleted up to -455. Therefore, we conclude that there are positive cis-elements at the region -1151 to -1008 and at -455 to -195 while the negative cis-element is at -1008 to -455.

• Journal of Nutrition and Health
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• v.45 no.6
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• pp.511-521
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• 2012

The purposes of this study were to assess the physical activity level (PAL) and the total daily energy expenditure (TEE) as well as to evaluate the validity of prediction equation for the estimated energy requirement (EER) in normal weight and overweight or obese children and adolescents. The subjects comprised of 100 healthy Korean students aged between 7-18. The anthropometric data was collected. PAL was calculated from the physical activity diary by the 24-hour recall method, and the resting metabolic rate (RMR) was measured by an open-circuit indirect calorimetry using a ventilated hood system. Daily energy expenditure was PAL multiplied by RMR. EER was calculated by using the prediction equation published in KDRIs. There was no significant difference in the means of age and height between the 46 obese subjects and 54 nonobese subjects. The weight and BMI of the obese group (60.2 kg, $25.3kg/m^2$) were significantly higher than those of the nonobese group (42.4 kg, $18.4kg/m^2$). However, PAL was not significantly different between the two groups (nonobese 1.45, obese 1.46). TEE of the obese group (2,212 kcal/day) was significantly higher than that of the nonobese group (1,774 kcal/day). EER (individual PA) and EER (light PA) were significantly higher than TEE (p < 0,001); however, EER (sedentary PA) was not significantly different with TEE in the two groups. These results showed that the levels of physical activity were the same as the sedentary activity both in the nonobese and obese Korean students; moreover, the predictive equation for EER published in KDRI overestimated the TEE of Korean children and adolescents. Therefore, in further research, a new predictive equation for EER should be developed for Korean children and adolescents through the doubly labeled water method.

• BMB Reports
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• v.32 no.2
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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.

• KSBB Journal
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• v.9 no.1
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• pp.26-34
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• 1994

When effects of exogenous hormone on hairy root cultures of Raphanus sativs cv. Chungpihongsim examined, the highest anthocyanin synthesis and disorganization were observed when 2, 4-D was supplemented to the culture medium Cytokinins showed early weak induction after transfer and ABA showed inhibitory effect and GA3 showed no effects in anthocyanin synthesis. Hormones except for 2, 4-D in 1 mg/$\ell$ concentration did not induce disorganization of hairy root and retarded growth of hairy root. Time-course changes in anthocyanin synthesis, phenylalanine ammonia-lyase activity and chalcone synthase activity were examined in culture condition contalning 2, 4-D and kinetin. In a medium containing 2, 4-D, anthocyanin synthesis began to increase on the 9th day and reaching maxima on the 18th day after transfer. Maximum peak of PAL activity appeared on the 3-9th day and another minor peak appeared on the 18th day. CHS activity increased from 9th day, reaching maximum on the 18th day and remained at a relatively high level for culture period. In a medium containing kinetin, anthocyanin synthesis increased temporarily on the 6-9th days, early days after transfer and maintained at a low level for remaining culture period. Peak of PAL activity appeared on the 6th day and CHS activity increased from the 6th days, reaching maxima about 18th day and remained at a relatively high level. In particular, addition of kinetin after preculture in hormone free medium for 2 weeks which was thought of wound healing period showed no effects in anthocyanin synthesis. This results showed that stimulation of anthocyanin synthesis by 2, 4-D and kinetin was meaningfully connected with changes of PAL, CHS activity, and then suggested rate-limiting role of CHS on anthocyanin synthesis in that there is close correlation between anthocyanin synthesis and changes of CHS activity in time-course. Besides, it is considered that cytoklnins involving kinetin stimulated anthocyanin synthesis be due to "wound response" by cutting of young roots, and that difference in time-course peak and PAL, CHS activities expressed by 2, 4-D and kinetin result from occurrence of isozyme which have different regulatory mechanism.mechanism.

• Journal of the Korean Dietetic Association
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• v.22 no.2
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• pp.131-142
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• 2016

The purpose of this study was to assess the physical activity and energy balance of weekdays and weekend in male high school students. Fifty healthy male high school students participated in this study. Anthropometric data were collected. Physical activity level (PAL) and energy intake for weekdays and weekend were calculated from a physical activity diary and food diary using the 24-hour recall method and interview. The resting metabolic rate (RMR) and estimated energy requirement (EER) were calculated from the prediction equations suggested in 2015 KDRIs. Total energy expenditure (TEE) was calculated by multiplying RMR by PAL. Mean age of subjects was $15.9{\pm}0.33years$. The daily pedometer counts were significantly higher in the weekdays (12,837 steps) than in weekend (6,661 steps) (P<0.001). The PAL of the weekdays ($1.63{\pm}0.17$) was significantly higher than that ($1.37{\pm}0.26$) of the weekend (P<0.001). PAL was significantly correlated with pedometer counts on the weekdays (r=0.495) and weekend (r=0.686). The total energy intakes ($2,847.2{\pm}681.5kcal$) and TEE ($3,046.3{\pm}437.3kcal$) of weekdays were significantly higher than those of the weekend. The results of this study would be useful to develop nutrition and exercise programs for male high school students on weekdays and weekend, respectively.