• Journal of Microbiology and Biotechnology
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• 제23권9호
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• pp.1293-1303
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• 2013

Antibiotic resistance of soilborne Acinetobacter species has been poorly explored. In this study, norfloxacin resistance of a soil bacterium, Acinetobacter oleivorans DR1, was investigated. The frequencies of mutant appearance of all tested non-pathogenic Acinetobacter strains were lower than those of pathogenic strains under minimum inhibitory concentration (MIC). When the quinolone-resistance-determining region of the gyrA gene was examined, only one mutant (His78Asn) out of 10 resistant variants had a mutation. Whole transcriptome analysis using a RNA-Seq demonstrated that genes involved in SOS response and DNA repair were significantly up-regulated by norfloxacin. Determining the MICs of survival cells after norfloxacin treatment confirmed some of those cells were indeed persister cells. Ten colonies, randomly selected from among those that survived in the presence of norfloxacin, did not exhibit increased MIC. Thus, both the low mutation frequency of the target gene and SOS response under norfloxacin suggested that persister formation might contribute to the resistance of DR1 against norfloxacin. The persister frequency increased without a change in MIC when stationary phase cells, low growth rates conditions, and growth-deficient dnaJ mutant were used. Taken together, our comprehensive approach, which included mutational analysis of the target gene, persister formation assays, and RNA sequencing, indicated that DR1 survival when exposed to norfloxacin is related not only to target gene mutation but also to persister formation, possibly through up-regulation of the SOS response and DNA repair genes.

• Parasites, Hosts and Diseases
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• 제40권1호
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• pp.17-24
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• 2002

We have cloned a cDNA encoding a cysteine proteinase of the Acanthamoeba healui OC-3A strain isolated from the brain of a granulomatous amoebic encephalitis patient. A DNA probe for an A. healui cDNA library screening was amplified by PCR using degenerate oligonucleotide primers designed on the basis of conserved amino acids franking the active sites of cysteine and asparagine residues that are conserved in the eukaryotic cysteine proteinases. Cysteine proteinase gene of A. healui (AhCPI) was composed of 330 amino acids with signal sequence, a proposed pro-domain and a predicted active site made up of the catalytic residues, $Cys^{25},{\;}His^{159},{\;}and{\;}Asn^{175}$. Deduced amino acid sequence analysis indicates that AhCPI belong to ERFNIN subfamily of C 1 peptidases. By Northern blot analysis. no direct correlation was observed between AhCPI mRNA expression and virulence of Acanthamoeba, but the gene was expressed at higher level in amoebae isolated from soil than amoeba from clinical samples. These findings raise the possibility that AhCPI protein may play a role in protein metabolism and digestion of phagocytosed bacteria or host tissue debris rather than in invasion of amoebae into host tissue.

• 한국수산과학회지
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• 제38권1호
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• pp.6-11
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• 2005

Vasopressin (VP)-related peptide was purified from the brain extract of conger eel (Conger myriaster) by reverse-phase, ion-exchange high performance liquid chromatography (HPLC). This peptide with a molecular weight of 1,051.2 Da was determined as $H-Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Arg-Gly-NH_2$, whose Cys residues made an intramolecular disulfide bridge by the automated amino acid sequence analysis, MALDI- TOF mass spectrometry. It's sequence was confirmed by identity of the elution position with the synthetic peptide in HPLC system. As a result of homology investigation, the primary structure of this peptide was the same as that of VP-superfamily member, $[Arg^8]-vasotocin$. The synthetic peptide showed a contractile activity at a minimal effective concentration of $10^{-10}\;M$ on the intestinal smooth muscle of goldfish.

• 생명과학회지
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• 제13권4호
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• pp.463-472
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• 2003

제5인자와 지질막 phosphatidylserine과의 상호작용은 prothrombinase 복합체의 활성을 조절하는데 중요하다. 본 연구에서 제5인자의 지질 결합부위에 위치한 Trp2063과 Trp2064를 동시에 돌연변이 시킨 재조합 제5인자를 과발현 시키고 정제하였다. 돌연변이된 제5인자는 1-10%의 phosphatidylserine을 포함하는 지질막에서 아주낮은 활성을 보였다. surface plasmon resonance에 의해서 지질막과의 결합을 측정한 결과 돌연변이된 제5인자가 본래의 제5인자보다 고정된 지질막에의 결합이 현저하게 떨어지는 것을 관찰하였다. 제5인자가 phosphatidylserine을 포함하는 지질막에 높은 친화력으로 결합하기 위해서는 Trp2063과 Trp2064가 필수적이고 이러한 상호작용은 생리적인 phosphatidylserine 농도를 포함하는 지질막 위에서 prothrombinase 복합체의 형성에 필요하다는 결론을 내렸다.

• 대한유전성대사질환학회지
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• 제19권1호
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• pp.20-25
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• 2019

Very-long-chain acyl-CoA dehydrogenase (VLCAD) 결핍증은 상염색체 열성으로 유전되는 유전성대사질환으로 미토콘드리아에서 장쇄지방산의 산화 장애이다. VLCAD 결핍증의 임상증상은 중증도 및 발현 시기에 따라 심각한 심장 이상을 동반하는 신생아기 발현형, 소아기 발현형, 지발형의 세 가지로 분류할 수 있다. 저자들은 혈장 아실카르니틴 분석과 유전자패널 염기서열분석 방법으로 확진된 성인기 발현형 VLCAD 결핍증 1례를 경험하였기에 보고하고자 한다. 34세 여자가 반복되는 근육통증과 간헐적 횡문근융해증의 병력을 주소로 내원하였다. 환자는 12세에 처음으로 운동 후 횡문근융해증으로 급성 신부전이 발생하여 혈액 투석을 받고 회복하였다. 이후 환자는 장시간의 운동이나 금식 후에 반복적으로 근육통증과 횡문근융해증이 발생하였다. 내원 시 신체 검진과 신경학적 검진은 정상이었다. 내원시 혈장 AST/ALT, Creatinine kinase (CK)는 약간 상승해있었으나, 이전 의무기록에 의하면 횡문근융해증이 있을 당시 AST/ALT, CK는 매우 상승하였다. 환자의 병력을 토대로 지방산대사장애 의심하에 감별진단을 위하여, 유전자 패널 염기서열 분석과 혈장 아실카르니틴 분석을 시행하였다. 혈장 아실카르니틴 분석결과 C14:1 ($1.453{\mu}mol/L$; 참고치, 0.044-0.285)와 C14:2 ($0.323{\mu}mol/L$; 0.032-0.301)가 증가였고, C14 ($0.841{\mu}mol/L$; 0.065-0.920)는 높은 정상이었다. 유전자패널 염기서열분석에서는 ACADVL 유전자에서 두 개의 병원성변이가 이형접합으로 발견되었으며, 이는 Sanger 염기서열 분석으로 확진되었다: c.[1202G>A(;)1349G>A] (p.[(Ser401Asn)(;)(Arg 450His)]). 환자는 생화학적, 유전학적 검사결과를 바탕으로 지발형 VLCAD 결핍증으로 확진되어 저지방식이와 급성 대사장애를 예방하기 위한 영양 교육을 받았다. 경증의 지발형 지방산 대사장애는 임상증상과 생화학적 검사 이상이 간헐적으로 발생하기 때문에 진단이 어렵다. 유전자패널 염기서열 분석은 지방산대사 장애와 같이 임상증상과 원인 유전자 이상이 다양한 대사 이상질환에서 유용한 진단법이 될 수 있다.

• 한국잠사곤충학회지
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• 제34권2호
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• pp.20-25
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• 1992

유용물질을 생산할 수 있는 곤충 baculovirus expression vector system의 국내 개발을 위하여, Bm-NPV의 다각체 단백질 유전자를 탐색, 클로닝 하고 그 구조를 분석한 결과는 다음과 같다. 1. AcNPV의 다각체 단백질 유전자를 포함하고 있는 EcoRI-Ⅰ fragment내의 0.93kb를 probe로 하여 southern 분석한 결과, BmNPV의 다각체 단백질 유전자는 PstⅠ-F fragment(7.4Kb)에 위치하였다. 2. BmNPV의 다각체 단백질 유전자를 포함하는 PstⅠ-F fragment를 E. coli에 클로닝시켜서 pBmP-F라 명명하고, 다시 southern분석을 통해 subcloning하여 pBmP-H라 명명하였으며 pBmP-H의 제한효소 지도를 작성하였다. 3. pBmP-H의 염기서열분석결과 구조유전자를 포함한 1,259 bp의 염기서열이 결정되었다. Iatrou 등이 보고한 BmNPV 다각체 단백질 유전자의 염기서열과 비교한 결과 10개의 염기서열에서 차이를 보였으며, 74 Val이 Ile로, 76 Asn이 Ser으로 155 Met이 Val로 아미노산 변경된 결과를 보였다.

• Toxicological Research
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• 제17권
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• pp.109-115
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• 2001

Abrus agglutinin was purified from the kernels of Abrus precatorius by Sepharose 4B affinity column chromatography followed by Sephadex G-100 gel filtration column chromatography. About 1.25 g of abrus agglutinin was obtained from 1 kg of the kernels. The LD$_{50}$ of abrus agglutinin is 5 mg/kg of body weight, which is less toxic than that of abrin, 20$\mu\textrm{g}$/kg body weight. The amino acid sequence of abrus agglutinin was determined by protein sequencing techniques and deduced from the nucleotide sequence of a cDNA clone encoding full length of abrus agglutinin. There are 258 residues, 2 residues and 267 residues in the A-chain, the linker peptide and the B-chain of abrus agglutinin, respectively. Abrus agglutinin had high homology to abrin-a (77.8%). The 13 amino acid residues involved in catalytic function, which are highly conserved among abrin and ricin, were also conserved within abrus agglutinin. The protein synthesis inhibitory activity of abrus agglutinin ($IC_{50}$/ = 3.5 nM) was weaker than that of abrin-a (0.05 nM). By molecular modeling followed by site-directed mutagenesis showed that Pro199 of abrus agglutinin A-chain located in amphipathic helix H and corresponding to Asn200 of abrin A-chain, can induce bending of helix H. This bending would presumably affect the binding of abrus agglutinin A-chain to its target sequence GpApGpAp, in the tetraloop structure of 285 r-RNA subunit and this could be one of major factors contributing to the relatively weak protein synthesis inhibitory activity and toxicity of abrus agglutinin.n.

• 한국ITS학회 논문지
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• 제12권3호
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• pp.29-41
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• 2013

본 연구는 교통정보센터와 노변장치간 국제표준 규격인 ISO 15784를 적용하여 국내 환경에 맞는 노변장치와 교통정보센터간 정보교환 표준 개발을 목표로 한다. 이를 위해 ISO 14817과 ISO 14827 Part 1을 참조하여 메시지 교환 시나리오 개념의 메시지 기본 개념과 시스템 구축 호환성 확보를 위해 명확히 정의가 필요한 필수 메시지 정의 항목을 정의하였다. AVI와 교통정보센터간 교환되는 실제 메시지 표준 개발을 위해 ITS 표준 기술위원회에 표준실무팀을 구성하여, ITS 아키텍쳐 정보흐름 분석, 국내 기 표준 분석, 현재 시내부와 국도상에 실제 설치되어 운영되고 있는 AVI 장비 메시지 프로토콜을 비교분석하여 총 14개의 기능 메시지를 정의하고, 이에 대해 DATEX 응용 프로토콜의 메시지 교환 시나리오에 따라 총 28개 메시지를 정의하였다. 데이터 교환을 위한 응용프로토콜은 ISO 15784의 참조표준을 분석하여 국내 현장장비와 교통정보센터간 데이터교환 환경을 고려한 상호운영성 및 상호호환성 확보를 위한 요구사항을 정의하였다.

• ALGAE
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• 제30권2호
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• pp.163-170
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• 2015

Tyrosinase inhibitors are an important component of cosmetic products. Our previous studies have proposed that eckol isolated from the brown alga Ecklonia cava, can be explored as a tyrosinase inhibitor. However, cellular activities and mechanism of action of eckol remain unknown. Therefore, the current study analyzed the eckol binding modes using the crystal structure of Bacillus megaterium tyrosinase. The effects of eckol on melanin synthesis induced by ${\alpha}$-melanocyte stimulating hormone in B16F10 melanoma cells were also investigated. We predicted the 3D structure of tyrosinase and used a docking algorithm to simulate binding between tyrosinase and eckol. These molecular modeling studies were successful (calculated binding energy value, $-115.84kcal\;mol^{-1}$) and indicated that eckol interacts with Asn205, His208, and Arg209. Furthermore, eckol markedly inhibited tyrosinase activity and melanin synthesis in B16F10 melanoma cells. We also found that eckol decreased the expression of tyrosinase, tyrosinase-related protein (TRP) 1, and TRP2. These results indicate that eckol is a potent inhibitor of melanogenesis, and this finding may be useful for the development of novel pharmaceutical and cosmetic agents.

• 한국축산식품학회지
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• 제31권3호
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• pp.356-365
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• 2011

We assessed the effects of single-nucleotide polymorphisms (SNPs) within the porcine fatty acid synthase (FASN) gene regarding meat quality and fatty acid composition in two pig populations: Korean native pigs (KNP) were crossed with Yorkshire (YS) $F_2$, and KNP were crossed with Landrace (LR) $F_2$. Direct DNA sequencing using eight KNP and eight YS pigs revealed two SNPs: c.265C>T (silent) in exon 4 and c.6545A>C (Asn${\rightarrow}$His) in exon 39. The frequency of the two SNPs was analyzed using the polymerase chain reaction-restriction fragment length polymorphism method in seven pig breeds and their association with meat quality traits and fatty acid composition was studied. In the $KNP{\times}YSF_2$ population, both SNPs were significantly associated with the level of monounsaturated fatty acids, including palmitoleic (C16:1) and oleic acid (C18:1) (p<0.005). c.6545A>C was associated with intramuscular fat content in both populations. Our results indicate that variations in c.265C>T and c.6545A>C of the pig FASN can be used to select animals with better fatty acid composition and meat quality. Moreover, KNP was a useful breed for identifying genetic factors affecting meat quality and fatty acid composition and for producing high quality pork.