• KSBB Journal
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• 제19권4호
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• pp.331-334
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• 2004

재조합 E. coli를 이용한 MCL-PHA의 생산에서 fatty acid pathway로부터 PHA 생합성 전구체 물질들이 만들어진다는 사실과 함께 이에 관여하는 enzymes이 밝혀지고 있다. 본 논문에서는 protein homology search로부터 탐색된 paaG와 ydbU genes의 PHA 생합성에서의 역할을 확인하기 위하여 paaG와 ydbU gene이 각각 knock-out된 mutant E. coli strains 를 제작하였다. 제작된 mutant E. coli들은 모균주들보다 낮은 PHA 농도와 함량을 가졌으며, 이러한 결과들로부터 paaG와 ydbU는 fatty acid pathway에서 PHA synthesis의 전구체 물질들을 공급한다는 사실을 확인하였다. 또한, 새로운 FadB homologous enzyme YgfG를 탐색하였으며, ygfG gene이 overexpression된 균주와 ygfG mutant를 제작하여 PHA 합성을 실험한 결과 ygfG도 paaG와 ydbU와 유사한 역할을 한다는 사실을 밝혔다. 이러한 연구결과들은 E. coli에서의 MCL-PHA 단량체들의 합성 경로를 확인하여 효과적인 PHA 생산 균주를 제작할 수 있게 할 것이다.

• Journal of Veterinary Science
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• 제22권4호
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• pp.42.1-42.16
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• 2021

Background: Inclusion body hepatitis (IBH) is an economically important viral disease primarily affecting broiler and breeder chickens. All 12 serotypes of fowl adenovirus (FAdV) can cause IBH. Objectives: To characterize FAdV isolates based on phylogenetic analysis, and to study the pathogenicity of FAdV-8b in specific-pathogen-free (SPF) chickens following virus inoculation via oral and intramuscular (IM) routes. Methods: Suspected organ samples were subjected to virus isolation and polymerase chain reaction (PCR) for FAdV detection. Hexon gene sequencing and phylogenetic analysis were performed on FAdV-positive samples for serotype identification. One FAdV-8b isolate, UPM/FAdV/420/2017, was selected for fiber gene characterization and pathogenicity study and was inoculated in SPF chickens via oral and IM routes. Results: The hexon gene phylogenetic analysis revealed that all isolates belonged to FAdV-8b. The fiber gene-based phylogenetic analysis of isolate UPM/FAdV/420/2017 supported the grouping of that isolate into FAdV species E. Pathogenicity study revealed that, chickens infected with UPM/FAdV/420/2017 via the IM route had higher clinical score values, higher percent mortality, higher degree of the liver lesions, higher antibody response (p < 0.05), and higher virus shedding amounts (p < 0.05) than those infected via the oral route. The highest virus copy numbers were detected in liver and gizzard. Conclusions: FAdV-8b is the dominant FAdV serotype in Malaysia, and pathogenicity study of the FAdV-8b isolate UPM/FAdV/420/2017 indicated its ability to induce IBH in young SPF chickens when infected via oral or IM routes.

• Journal of Applied Biological Chemistry
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• 제65권3호
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• pp.203-213
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• 2022

미선나무(Abeliophyllum distichum) 1속 1종의 한반도 고유식물이다. 꽃잎색의 변이에 따라 미선(백색), 분홍미선, 상아미선 그리고 연노랑색의 옥황1호 품종 등으로 구분된다. 본 연구에서는 4종류의 꽃 추출물(FAD)로부터 생리활성물질의 함량과 항염증 활성 차이를 비교·분석하였다. FAD의 생리활성 물질은 LC/MS 분석을 통해 rutin, hirsutrin, 그리고 acteoside를 분석하였다. DPPH와 ABTS 라디칼 소거활성을 통한 항산화 활성을 분석하였으며, 항산화 활성은 각 추출물의 생리활성 물질의 함량에 따라 유의성 있는 활성을 나타내었다. FAD는 LPS로 유도된 RAW 264.7 세포에서 염증 유발 매개체(산화질소, iNOS, COX-2)의 발현을 감소시켰다. 또한 NF-κB와 MAPK 신호전달 경로 조절을 통한 항염증 효과를 확인하였다.

• 한국식품영양과학회지
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• 제4권1호
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• pp.1-6
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• 1975

After ablactation, wistar strain white male rats, weighing 270g and 340g, were fed with a diet of CLEA for three months. The whole daily excretion of each feces and urine were collected, and extracted with water($80^{\circ}C$ hot water). The combined extraction were filtered and the $B_2$ was determined with the parts of the filterates by the lumiflavin fluorometric method, and the FMN, FAD and FR with the rest of the filterates by paper chromatography. The following results were obtained; 1. $B_2$ contents in the feces were $27.52{\gamma}$ per 100 grams per body weight, and $83.93{\gamma}$ per each rat per day. 2. $B_2$ contents in the urine were $18.47{\gamma}$ per 100 grams per body weight, and $56.33{\gamma}$ per each rat per day. The total daily excretion of $B_2$ contents in the feces were 1. 5 times as much as in the urine. 3. Among the total daily $B_2$ excretion of one white wistar strain rat in the feces were the following ; FAD, 81.0% ; FMN, 14.9% ; FR, 3.3%. Therefore the order of the contents were FAD>FMN>FR.

• Journal of Microbiology and Biotechnology
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• 제23권10호
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• pp.1413-1421
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• 2013

The marine microalga Isochrysis sphaerica is rich in the very-long-chain polyunsaturated fatty acids, including eicosapentaenoic acid (EPA, $C20:5{\omega}-3$) and docosahexaenoic acid (DHA, $C22:6{\omega}-3$) that are important to human health. Here, we report a functional characterization of a ${\Delta}4$-fatty acid desaturase gene (FAD4) from I. sphaerica. IsFAD4 contains a 1,284 bp open reading frame encoding a 427 amino acid polypeptide. The deduced amino sequence comprises three conserved histidine motifs and a cytochrome b5 domain at its N-terminus. Phylogenetic analysis indicated that IsFad4 formed a unique Isochrysis clade distinct from the counterparts of other eukaryotes. Heterologous expression of IsFAD4 in Pichia pastoris showed that IsFad4 was able to desaturate docosapentaenoic acid (DPA) to form DHA, and the rate of converting DPA to DHA was 79.8%. These results throw light on the potential industrial production of specific polyunsaturated fatty acids through IsFAD4 transgenic yeast or oil crops.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XIII)
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• pp.600-600
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• 2003

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.24-24
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• 2022

This present study was to identify a novel candidate gene that contribute to the elevated α-linolenic acid (ALA, ω-3) concentration in PE2166 from mutagenesis of Pungsannamul. Major loci qALA5_1 and qALA5_2 were detected on chromosome 5 of soybean through quantitative trait loci mapping analyses of recombinant inbred lines. With next generation sequencing of parental lines and Pungsannamul, and recombinant analyses, a potential gene, Glyma. 05g221500 (HD) controlling elevated ALA concentration was identified. HD is a homeodomain-like transcriptional regulator that may regulate the expression level of microsomal ω-3 fatty acid desaturase (FAD3) genes responsible for the conversion of linoleic acid into ALA in the fatty acid biosynthetic pathway. In addition, we hypothesized that combination of mutant alleles, HD and either of microsomal delta-12 fatty acid desaturase 2-1 (FAD2-1\ could reduce the ω-6/ω-3 ratio. In populations where HD, and FAD2-1A and FAD2-1B genes were segregated, combination of a hd allele from PE2166 and either of the variant FAD2-1 alleles were sufficient to reduce the ω-6/ω-3 ratio in seeds.

• BMB Reports
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• 제40권1호
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• pp.53-57
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• 2007

The enzymatic properties of NADH:quinone oxidoreductase were examined in Triton X-100 extracts of Bacillus cereus membranes by using the artificial electron acceptors ubiquinone-1 and menadione. Membranes were prepared from B. cereus KCTC 3674 grown aerobically on a complex medium and oxidized with NADH exclusively, whereas deamino-NADH was determined to be poorly oxidized. The NADH oxidase activity was lost completely by solubilization of the membranes with Triton X-100. However, by using the artificial electron acceptors ubiquinone-1 and menadione, NADH oxidation could be observed. The activities of NADH:ubiquinone-1 and NADH:menadione oxidoreductase were enhanced approximately 8-fold and 4-fold, respectively, from the Triton X-100 extracted membranes. The maximum activity of FAD-dependent NADH:ubiquinone-1 oxidoreductase was obtained at about pH 6.0 in the presence of 0.1M NaCl, while the maximum activity of FAD-dependent NADH:menadione oxidoreductase was obtained at about pH 8.0 in the presence of 0.1M NaCl. The activities of the NADH:ubiquinone-1 and NADH:menadione oxidoreductase were very resistant to such respiratory chain inhibitors as rotenone, capsaicin, and $AgNO_3$, whereas these activities were sensitive to 2-heptyl-4-hydroxyquinoline-N-oxide (HQNO). Based on these results, we suggest that the aerobic respiratory chain-linked NADH oxidase system of B. cereus KCTC 3674 possesses an HQNO-sensitive NADH:quinone oxidoreductase that lacks an energy coupling site containing FAD as a cofactor.

• Journal of Veterinary Science
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• 제19권6호
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• pp.759-770
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• 2018

Fowl adenovirus (FAdV) is distributed worldwide and causes economic losses in the poultry industry. The objectives of this study were to determine the hexon and fiber gene changes in an attenuated FAdV isolate from Malaysia in specific pathogen-free chicken embryonated eggs (SPF CEE) and its infectivity in commercial broiler chickens. SPF CEE were inoculated with 0.1 mL FAdV inoculum via the chorioallantoic membrane (CAM) for 20 consecutive passages. The isolate at passage 20 (E20), with a virus titer of $10^{8.7}TCID_{50}/mL$ ($TCID_{50}$, 50% tissue culture infective dose), was inoculated (0.5 mL) into one-day-old commercial broiler chicks either via oral or intraperitoneal routes. The study demonstrated that 100% embryonic mortality was recorded from E2 to E20 with a delayed pattern at E17 onwards. The lesions were confined to the liver and CAM. Substitutions of amino acids in the L1 loop of hexon at positions 49 and 66, and in the knob of fiber at positions 318 and 322 were recorded in the E20 isolate. The isolate belongs to serotype 8b and is non-pathogenic to broiler chickens, but it is able to induce a FAdV antibody titer. It appears that molecular changes in the L1 loop of hexon and the knob of fiber are markers for FAdV infectivity.

• Journal of Microbiology and Biotechnology
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• 제19권4호
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• pp.362-367
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• 2009

In recombinant strains, many proteins and enzymes are expressed as inactive and insoluble inclusion bodies. For soluble expression of an active form of StyB, an NADH-flavin oxidoreductase, several recombinant Escherichia coli strains were developed and tested. Among them, strain BL21(DE3)pLysS effectively produced an active and soluble form of StyB as about 9% of the total protein content, when cultivated at $20^{\circ}C$ with 0.5 mM IPTG. The solubly expressed StyB has the highest oxidoreductase activity at pH 6.5-7.5 and $37^{\circ}C$. Substrate dependence profiles of the StyB-catalyzed reaction showed that the maximum specific activity($V_m$) and half saturation constant($K_m$) were $1,867{\pm}148\;U/mg$ protein and $51.6{\pm}11{\mu}M$ for NADH, and $1,274{\pm}34\;U/mg$ protein and $8.2{\pm}1.2{\mu}M$ for FAD, respectively. This indicates that solubly produced StyB has 6- to 9-fold higher oxidoreductase activities than the in vitro refolded StyB from inclusion bodies.