• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.276-276
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• 2022

Wheat is one of the most widely grown food crops worldwide. Extreme precipitation and wind disturbances increased due to the abnormal climate, which resulted in increased lodging. Introduction of dwarf genes in wheat significantly increased lodging resistance and productivity in wheat breeding. In this study, we performed the genotyping of dwarfing genes between 'Keumkang' and 'Komac 5' ('Keumkang' mutant). In addition, we investigated the relationship between plant height and several phenotypic characters using F₂ segregation populations derived from crosses between the two varieties. There was no significant difference in phenotypic characters between the two varieties except for plant height. In the genotyping analysis using dwarfing genes, mutations of two dwarfing gene were found to be induced between the two varieties. The four genotypes of the F₂ populations from a crossing between 'Keumkang' and 'Komac 5' were used to compare and evaluate the effects of two dwarfing genes. Plants with two single mutant dwarfing gene and double mutant dwarfing gene revealed reduced plant heights than control plants by 4.5%, 6.9%, and 33.2%, respectively. The phenotype analysis showed that double mutant dwarfing gene affected wheat stem growth as the length decreases from the second node, resulting in decreased plant height. However, there were no significant differences in the agronomic traits between mutant plants and control plant. These results may provide novel information about the effect of double mutant dwarfing gene on plant height, and may help improve lodging tolerance and wheat yield.

• 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.

• KSBB Journal
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• 제9권1호
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• pp.16-25
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• 1994

Bacillus subtilis를 재조합 이종 단백질 생산 균주로 만들기 위하여 포자형성 변이주를 만들었다. 균주는 두 개의 프로테아제가 제거된 균주인 DB104로부터 spoOJ와 spoIIG 변이주를 유전자 조작법에 의해 만들고 두 개의 유전자가 모두 제거된 균주도 만들었다. 이에 목적 aprE 유전자를 삽입 벡터 형태로 만들어 integration시킨 뒤 변이주 각각의 형태적인 변화를 투과성 전자현미경으로 살펴 보았다. 각각 변이주의 모습은 이전에 보고된 것과 거의 일치하였으며 spoOJ spoIIG 이중포자변이주의 경우는 spoIIG 변이주와 더욱 닮은 것을 알 수 있었으며, 훨씬 주름진 것과 같은 투박한 세포벽 및 막을 가지고 있음을 관찰하였다. spoOJ 변이는 포자형성 빈도를 낮추고 aprE 활성을 감소시키는 반면, spoIIG 변이는 포자형성을 거의 하지 않으면서 aprE 활성에 상승효과를 가져왔다. spoOJ와 spoIIG 이중포자변이주는 spoOJ 변이의 효과는 거의 나타나지 않은채, spoIIG와 비슷한 aprE 활성을 보였다.

• Fisheries and Aquatic Sciences
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• 제14권2호
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• pp.73-78
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• 2011

Vibrio parahaemolyticus possesses two flagella systems: polar and lateral flagella for swimming in liquid and swarming on solid surfaces or in viscous environments. To elucidate the pathogenic role of these dual flagella systems, we constructed single- and double-deletion mutants of the lafA and flhAB flagellum genes and investigated their biofilm formation, cell adhesion, and colonization of the small intestine of suckling mice. The double-mutant strain was more impaired in biofilm formation than either of the single-mutant strains. In addition, the lafA, flhAB, and double-mutant strains showed 40%, 45%, and 60%, respectively, lower adherence to HeLa cells than the wild-type strain. Moreover, the lafA, flhAB, and double-mutant strains exhibited 49%, 5.6 and 6.7 times, respectively, lower colonization in a competition assay than the wild-type strain. These findings indicated that polar flagella were more important than lateral flagella for the pathogenesis of V. parahaemolyticus.

• Molecules and Cells
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• 제19권2호
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• pp.219-222
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• 2005

The a-subunit of Escherichia coli tryptophan synthase (${\alpha}TS$), a component of the tryptophan synthase ${\alpha}_2{\beta}_2$ complex, is a monomeric 268-residues protein (Mr = 28,600). ${\alpha}TS$ by itself catalyzes the cleavage of indole-3-glycerol phosphate to glyceraldehyde-3-phosphate and indole, which is converted to tryptophan in tryptophan biosynthesis. Wild-type and P28L/Y173F double mutant ${\alpha}$-subunits were overexpressed in E. coli and crystallized at 298 K by the hanging-drop vapor-diffusion method. X-ray diffraction data were collected to $2.5{\AA}$ resolution from the wild-type crystals and to $1.8{\AA}$ from the crystals of the double mutant, since the latter produced better quality diffraction data. The wild-type crystals belonged to the monoclinic space group C2 ($a=155.64{\AA}$, $b=44.54{\AA}$, $c=71.53{\AA}$ and ${\beta}=96.39^{\circ}$) and the P28L/Y173F crystals to the monoclinic space group $P2_1$ ($a=71.09{\AA}$, b=52.70, $c=71.52{\AA}$ and ${\beta}=91.49^{\circ}$). The asymmetric unit of both structures contained two molecules of ${\alpha}TS$. Crystal volume per protein mass ($V_m$) and solvent content were $2.15{\AA}^3\;Da^{-1}$ and 42.95% for the wild-type and $2.34{\AA}^3\;Da^{-1}$ and 47.52% for the double mutant.

• 약학회지
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• 제41권6호
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• pp.756-764
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• 1997

Ile-224 in I269S mutant horse liver alcohol dehydrogenase isoenzyme S (HLADH-S) was mutated to serine by site-directed mutagenesis in order to study the role of the residue in c oenzyme binding to the enzyme. The specific activity of the I269S and I224S mutant enzyme to ethanol was increased 6-fold and all Michaelis constants($K_a,\;K_b,\;K_p,\;and\;K_q$,/TEX>) were larger than those for the wild-type and I269S enzyme. The substitution decreased the afffinity to coenzymes and increased the specific activity of the enzyme. The mutant enzyme showed the highest catalytic efficiency for octanol among the primary alcohols. But it didn`t have activities on retinoids and 5${\beta}$-cholanic acid-3-one. From these results, it was confirmed that the hydrophobic interaction of Ile-224 residue with coenzyme was related to coenzyme affinity in ADH reaction. The substitution also affected the substrate affinities to the enzyme.

• Journal of Nutrition and Health
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• 제33권5호
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• pp.491-496
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• 2000

Food intake is regulated by both central and peripheral mechanisms. In the central nervous, the hypothalamus acts for autonomic and endocrine homeostasis. The paraventricular nucleus(PVN) of hypothalamus is an imprtant site of interaction in central feeding pathways. Neuroepetide Y(NPY)is one of the most powerful neurochemical stimulants of food intake known. Also brain nitric oxide(NO), known as neurotransmitter, is involved in the mechanisms that regulate food intake. In this experiment, 24h fasting mice and anorexia mutant mice have been to examine the expression of NPY, which is the major neuropeptide increasing food intake. Double staining with NPY and nicotinamide-adenine-dinucleotide-phosphate diaphorase(NADPH-d), followed by immunohistochemical method and image analysis, have been used to observe coexisting neurons and the level of expression of each neurons. The results were as follows. 1) NPY-immunoreactivitys reduced immune response of the hypothalamus, particularly paraventricular nucleus(PVN), in anorexia mutant mice. Decreased level of NPY is assumed to be a major pathological factor in anorexia mutant mice. On the other hand, PVN in hypothalamus of fasting mice showed increased immunoreactivity which is in agreement of other researchers. 2) NPY and NADPH-d double staining revealed coexisting neurons in the cerebral cortex. Fasting mice had a tendency to have increased level of coexisting neurons compared to the control group. Compared to the control group, fasting mice express is not increase level of NPY-immunoreactivity, while anorexia mutant mice tended to have a decreased level.

• 생명과학회지
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• 제12권4호
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• pp.464-468
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• 2002

대장균 트립토판 중합효소(tryptophan synthase) $\alpha$ 소단 위체의 96번, 139번 과 258번 자리를 돌연변이 시킨 이중 돌연변이체 P96L/F139W, P6L/F258W와 삼중 돌연변이체 P96L/F139W/F258W의 효소 활성도와 형광 분광계를 이용한 분광학적 성질을 조사하였다. 이중 돌연변이체의 효소 활성도는 야생형과 유사하나 삼중 돌연변이체는 40% 감소된 활성도를 가진다. P96L/F139W 와 P96L/F258W의 형광세기는 야생형에 비해 감소하였으나 P96L/F139W/F258W는 야생형에 비해 증가하였다. 효소 활성도와 형광 결과는 96번의 치환이 8번 알파구조와 4번 베타 구조와 4번 알파구조 사이의 loop의 안정성에 영향을 준 것을 나타낸다. 이 결과로부터 P96L/F139W/F258W는 야생형과 다른 3차 구조를 가지나 139번과 258면 주위는 더 조밀한 구조를 가지고 있다는 것을 보여준다.

• Journal of Microbiology and Biotechnology
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• 제29권3호
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• pp.373-381
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• 2019

Site-directed mutagenesis was employed to generate five different triple point mutations in the double mutant (C295A/I86A) of Thermoanaerobacter ethanolicus alcohol dehydrogenase (TeSADH) by computer-aided modeling with the aim of widening the small alkyl-binding pocket. TeSADH engineering enables the enzyme to accept sterically hindered substrates that could not be accepted by the wild-type enzyme. The underline in the mutations highlights the additional point mutation on the double mutant TeSADH introduced in this work. The catalytic efficiency ($k_{cat}/K_M$) of the ${\underline{M151A}}$/C295A/I86A triple TeSADH mutant for acetophenone increased about 4.8-fold higher than that of the double mutant. A 2.4-fold increase in conversion of 3'-methylacetophenone to (R)-1-(3-methylphenyl)-ethanol with a yield of 87% was obtained by using ${\underline{V115A}}$/C295A/I86A mutant in asymmetric reduction. The ${\underline{A85G}}$/C295A/I86A mutant also produced (R)-1-(3-methylphenyl)-ethanol (1.7-fold) from 3'-methylacetophenone and (R)-1-(3-methoxyphenyl)-ethanol (1.2-fold) from 3'-methoxyacetophenone, with improved yield. In terms of thermal stability, the ${\underline{M151A}}$/C295A/I86A and ${\underline{V115A}}$/C295A/I86A mutants significantly increased ${\Delta}T_{1/2}$ by $+6.8^{\circ}C$ and $+2.4^{\circ}C$, respectively, with thermal deactivation constant ($k_d$) close to the wild-type enzyme. The ${\underline{M151A}}$/C295A/I86A mutant reacts optimally at $70^{\circ}C$ with almost 4 times more residual activity than the wild type. Considering broad substrate tolerance and thermal stability together, it would be promising to produce (R)-1-(3-methylphenyl)-ethanol from 3'-methylacetophenone by ${\underline{V115A}}$/C295A/I86A, and (R)-1-phenylethanol from acetophenone by ${\underline{M151A}}$/C295A/I86A mutant, in large-scale bioreduction processes.

• Journal of Plant Biotechnology
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• 제38권2호
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• pp.169-175
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• 2011

칼슘은 동물과 마찬가지로 식물에서도 다양한 신호를 전달하는 2차 매개체로 잘 알려져 있다. 특히, 세포사멸 현상을 유도하는 신호전달에 칼슘의 관여는 잘 보고되어 있다. 최근 발표된 논문에서 액포막에 존재하는 $Ca^{2+}$-ATPases(ACA4와 ACA11)가 이중으로 돌연변이된 식물체의 잎에서 세포사멸 표현형을 관찰했으며, 이러한 세포사멸 현상이 salicylic acid (SA)에 의존적이라고 보고했다. 또한 앞선 연구들에서 vacuolar processing enzymes (VPEs)이 생물학적 또는 비생물학적 스트레스에 의해서 유발되는 SA에 의해서 활성화 된다고 보고하였다. 본 연구에서는 액포막 $Ca^{2+}$-ATPases (ACA4와 ACA11)가 이중으로 돌연변이 된 식물체에서 VPEs의 유전자 발현이 상당히 증가되어 있고 효소 활성도 증가됨을 확인했다. 이 결과를 바탕으로, aca4/aca11/avpe와 aca4/aca11/${\gamma}$vpe 그리고, aca4/aca11/avpe/${\gamma}$vpe의 삼중과 사중 돌연변이체를 구축했다. 이들과 aca4/aca11의 이중 돌연변이체의 세포사멸 표현형을 비교 관찰한 결과, 삼중과 사중 돌연변이에서 세포사멸 현상이 일정기간 억제되는 것을 관찰했다. 또한, 삼중과 사중의 돌연변이체에서 VPEs의 효소 활성이 많이 감소되는 현상으로 나타났다. 결론적으로, $Ca^{2+}$-ATPases (ACA4와 ACA11)가 이중으로 돌연변이된 식물체에서는 SA가 유발되며, 이러한 SA에 의해서 VPEs의 단백질이 활성화되어 세포사멸 현상이 발생할 것으로 사료된다.