• 한국미생물·생명공학회지
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• 제46권2호
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• pp.91-101
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• 2018

The aim of this study was to transfer the 18.5 kb gene clusters coding for 17 genes from Lactobacillus rhamnosus to Lactococcus lactis subsp. cremoris MG1363 in order to determine the effect of host on exopolysaccharide (EPS) production and to provide a model for studying the phosphorylation of proteins which are proposed to be involved in EPS polymerization. Lactobacillus rhamnosus RW-9595M and ATCC 9595 have 99% identical operons coding for EPS biosynthesis, produced different amounts of EPS (543 vs 108 mg/l). L. lactis subsp. cremoris MG1363 transformed with the operons from RW-9595M and ATCC 9595 respectively, produced 326 and 302 mg/l EPS in M17 containing 0.5% glucose. The tyrosine protein kinase transmembrane modulator (Wzd) was proposed to participate in regulating chain elongation of EPS polymers by interacting with the tyrosine protein kinase Wze. While Wzd was found in phosphorylated form in the presence of the phosphorylated kinase (Wze), no phosphorylated proteins were detected when all nine tyrosines of Wzd were mutated to phenylalanine. Lactococcus lactis subsp. cremoris could produce higher amounts of EPS than other EPS-producing lactococci when expressing genes from L. rhamnosus. Phosphorylated Wzd was essential for the phosphorylation of Wze when expressed in vivo.

• Journal of Ginseng Research
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• 제9권1호
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• pp.24-35
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• 1985

Rusty root of ginseng has been known as one of the limiting factors in ginseng production in Korea. An attempt was, therefore, made to elucidate biological and chemical natures of the rusty root, and the redox Potential of the ginseng cultivated soils were measured and compared with diseased and non-diseased soils. Reddish discoloration was most frequently observed on the epidermis of ginseng root and the pigments were accumulated in all epidermal cells of the diseased lesions. The lower the redox potential of the ginseng cultivated soil was, the more severe the rusty root was observed. Fe content in the diseased epidermis was 3 times higher than that of healthy one. Organic acids such as oxalic, malonic, succinic, and citric acids were also higher in the mss root than in the healthy one. Thin layer chromatogram of phenolic acid fractions obtained from the epidermal cells of the rusty root of ginseng exhibited 3 to 4 unidentified substances not found in the healthy root. Also lignification of the epidermal cells and the activity of phenylalanine ammonia lyase were greater in the rusty root than the healthy root. Colony formation and conidia production of F. solani, And mycelial growth and sclerotium formation of Sclerotinia sp. isolated from ginseng root were suppressed in a nutritionally minimal medium supplemented with water extract of rusty ginseng root epidermis. It is, therefore, suggested that rusty root of ginseng is caused by unfavorable rhizosphere environmental stress or stresses resulting abnormal metabolism in the root as a selfdefence mechanism of non-specific resistance responses.

• Asian-Australasian Journal of Animal Sciences
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• 제6권3호
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• pp.339-342
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• 1993

This influence of dietary medium chain triglyceride on liver protein synthesis in chicks was investigated using a large dose injection of $L-[4-^3H]$ phenylalanine. Dietary medium chain triglyceride increased liver weight and liver fat content of chicks compared to the long chain triglyceride group. Fractional synthesis rate of liver protein was increased by dietary medium chain triglyceride, which was accounted for not by elevating protein synthesized per unit RNA but by enhancing RNA: protein ratio.

• Asian-Australasian Journal of Animal Sciences
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• 제9권2호
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• pp.171-174
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• 1996

Muscle protein synthesis in vitro was measured in chicks fed low-protein(10% CP) and control(20% CP) diets. Right leg muscles (M. gastrocnemius) were mounted on a support made of stainless steel to stretch in constant tension, whereas left leg muscles were unmounted. Both leg muscles were incubated in Dulbecco's modified Eagle's medium including L-[$4-^3H$] phenylalanine for 60 min to measure in vitro protein synthesis. There was no significant difference in fractional synthesis rate(FSR) of muscle protein between both dietary protein levels, whereas FSR with stretch in constant tension was significantly higher than that without constant tension due to an increase in the absolute synthesis rate(ASR) per unit RNA(the efficiency of RNA to synthesize protein). The ASR of muscle protein in chicks fed the control diet was significantly higher than that in the low-protein diet group.

• Natural Product Sciences
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• 제21권4호
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• pp.255-260
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• 2015

Two new thiodiketopiperazines (TDKPs), designated graphiumins I (1) and J (2), were isolated from the culture broth of the marine-derived fungus Graphium sp. OPMF00224 by solvent extraction, silica gel column chromatography, and HPLC. Their absolute structures were elucidated by spectroscopic analyses (1D and 2D NMR data, ROESY correlations, and CD data) and chemical methods. They were found to be structurally rare TDKPs with a phenylalanine-derived indolin substructure. Compounds 1 and 2 inhibited yellow pigment production by methicillin-resistant Staphylococcus aureus (MRSA) with $IC_{50}$ values of 63.5 and $76.5{\mu}g/ml$, respectively, without inhibiting its growth, even at $250{\mu}g/ml$.

• 폴리머
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• 제35권5호
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• pp.424-430
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• 2011

Biodegradable poly[(glycine ethyl ester)-(phenylalanine ethyl ester) phosphazene](PGPP) microparticles were fabricated by electrohydrodynamic atomization to apply drug release test. Atomization parameters such as applied voltage, polymer concentration, and molecular weight were investigated to inspect their effects on the size and morphology of microparticles. The average diameter of PGPP microparticles decreased as increasing applied voltage and solution flow rate. Dichloromethane/dioxane mixture shows better results for the preparation of microparticles than single solvent owing to the different PGPP solubility in solvent. Blending PGPP polymers with proper molecular weights not only favored the production of spherical PGPP microparticles via electrohydrodynamic atomization, but also provided a way to adjust drug (rifampicin) release behavior. Drug-loaded biodegradable polyphosphazene microspheres can be fabricated via electrohydrodynamic atomization, which has potential use in biomedical applications.

• The Plant Pathology Journal
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• 제36권5호
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• pp.476-490
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• 2020

The parasitic weed, Orobanche crenata, is one of the most devastating constraint for faba bean production in Mediterranean regions. Plant host defense induction was reported as one of the most appropriate control methods in many crops. The aim of this study was to elucidate the effect of salicylic acid (SA) and indole acetic acid (IAA) on the induction of faba bean resistance to O. crenata under the field and controlled experimental conditions. Both hormones were tested on two contrasting faba bean genotypes: Giza 843 (partially resistant to O. crenata) and Lobab (susceptible) at three different application methods (seed soaking, foliar spray, and the combination of both seed soaking and foliar spray). Soaking seeds in SA or IAA provided the highest protection levels reaching ~75% compared to the untreated control plants. Both elicitors limited the chlorophyll content decrease caused by O. crenata infestation and increased phenolic compound production in host plants. Phenylalanine ammonia lyase, peroxidase, and polyphenol oxidase activities were stimulated in the host plant roots especially in the susceptible genotype Lobab. The magnitude of induction was more obvious in infested than in non-infested plants. Histological study revealed that both SA and IAA decreased the number of attached O. crenata spikes which could be related to specific defense responses in the host plant roots.

• Animal Bioscience
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• 제36권11호
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• pp.1757-1768
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• 2023

Objective: The number of bovine mammary epithelial cells (BMECs) is closely associated with the quantity of milk production in dairy cows; however, the optimal levels and the combined effects of hormones and essential amino acids (EAAs) on cell proliferation are not completely understood. Thus, the purpose of this study was to determine the optimal combination of individual hormones and EAAs for cell proliferation and related signaling pathways in BMECs. Methods: Immortalized BMECs (MAC-T) were treated with six hormones (insulin, cortisol, progesterone, estrone, 17β-estradiol, and epidermal growth factor) and ten EAAs (arginine, histidine, leucine, isoleucine, threonine, tryptophan, lysine, methionine, phenylalanine, and valine) for 24 h. Results: Cells were cultured in a medium containing 10% fetal bovine serum (FBS) as FBS supplemented at a concentration of 10% to 50% showed a comparable increase in cell proliferation rate. The optimized combination of four hormones (insulin, cortisol, progesterone, and 17β-estradiol) and 20% of a mixture of ten EAAs led to the highest cell proliferation rate, which led to a significant increase in cell cycle progression at the S and G2/M phases, in the protein levels of proliferating cell nuclear antigen and cyclin B1, cell nucleus staining, and in cell numbers. Conclusion: The optimal combination of hormones and EAAs increased BMEC proliferation by enhancing cell cycle progression in the S and G/2M phases. Our findings indicate that optimizing hormone and amino acid levels has the potential to enhance milk production, both in cell culture settings by promoting increased cell numbers, and in dairy cows by regulating feed intake.

• KSBB Journal
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• 제24권1호
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• pp.75-79
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• 2009

Coenzyme $Q_{10}$ 고역가 변이주인 Agrobacterium tumefaciens KPU-11-03의 다양한 유기 질소원에 대한 coenzyme $Q_{10}$ 생산량과 coenzyme $Q_{10}$의 구성비율 등을 비교한 결과, CSP 첨가 시 coenzyme $Q_{10}$ 생산량은 212.7 mg/l, 구성비율은 94%로 다른 유기질소원에 비해 매우 높게 나타났다. 특히 Bacto tryptone, Bacto peptone, soybean meal, casamino acid 등의 유기 질소원 첨가 시에는 극히 낮은 coenzyme $Q_{10}$ 역가를 나타내어 균체내의 coenzyme $Q_{10}$의 축적은 유기 질소원의 종류 즉 아미노산의 종류 및 량과 상관성이 있음을 추정할 수 있었다. 또한 무기질소원에 대하여 실험한 결과, $(NH_4)_2SO_4$ 첨가 시에 coenzyme $Q_{10}$역가가 약 2배 증가하였고 다른 무기질소원에 사용 시에는 오히려 감소하였다. Coenzyme $Q_{10}$ 역가와 관련된 아미노산을 확인하기 위해 유기질소원으로 Bacto tryptone을 첨가한 배지에 9가지의 아미노산을 첨가하여 실혐한 결과, 방향족 아미노산인 tyrosine 첨가 시의 coenzyme $Q_{10}$ 생산량은 99.5 mg/l로 비첨가구보다 약 8.2배 증가하였으나 phenylalanine과 tryptophan등의 다른 방향족 아미노산의 첨가 시에는 coenzyme $Q_{10}$ 생산량이 오히려 감소하는 것으로 나타나 tyrosine의 첨가가 coenzyme $Q_{10}$ 역가에 매우 중요함을 확인하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제7권1호
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• pp.113-117
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• 1994

The effect if heat treatment (autoclave) in amino acid digestibility of winged bean determined using intact cockerels had been investigated. The winged beans were autoclaved at $120^{\circ}C$ for 45 or 90 min, respectively, and the soybean were autoclaved for 45 min. The treated winged bean and soybean were fed to 3 intact cockerels, which had been previously starved for 24 h. Excreta were collected individually for 49 h. The amino acids contained in the diets and excreta were determined to measure the digestibility values. Apparent and true digestibilities of all amino acids except histidine of unheated winged bean were significantly (P < 0.05) lower than those of heated winged bean and soybean. Heat treatment significantly (p < 0.05) improved amino acid digestibility of winged bean, However, over heating (90 min if autoclaving) destroyed lysine, cystine and arginine of winged bean. The true digestibility values of all amino acids of winged bean heated for 90min were the same as those values of treated soybean. However, true digestibilities of glycine, alannine, phenylalanine and lysine of treated soybean were significantly (p < 0.05) higher than those of winged bean heated for 45 min.