• Animal cells and systems
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• 제8권3호
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• pp.205-212
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• 2004

The tumor suppressor protein p53 is stabilized by the herpes-virus-associated ubiquitin-specific protease (HAUSP), a deubiquitinating enzyme. We previously isolated and characterized a mouse orthologue of HAUSP, mHAUSP. mHAUSP cDNA consisted of 3,312 bp encodes 1,103 amino acids with a molecular weight of approximately 135 kDa containing highly conserved Cys, Asp (I), His, and Asn/Asp (II) domains. In this study, we carried out site-directed mutagenesis of 6 conserved amino acids (Cys224, Gln231, Asp296, His457, His465, and Asp482) in Cys box, QQD box, and His box. Interestingly, the conserved Gln 231 was not essential for the catalytic activity of mHAUSP. However, the other conserved amino acids were required for deubiquitinating activity of mHAUSP. We performed isopeptidase assay and confirmed that mHAUSP is able to remove ubiquitin from ubiquitinated substrates. In addition, we observed that mHAUSP induces apoptosis in HeLa cells.

• 대한의생명과학회지
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• 제13권2호
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• pp.105-110
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• 2007

Aspartyl-tRNA synthetase (AspRS) exists in two different forms with respect to tRNA recognition. The discriminating enzyme (D-AspRS) recognizes only tRNA$^{Asp}$, while the non-discriminating one (ND-AspRS) also recognizes tRNA$^{Asn}$ and therefore forms both Asp-tRNA$^{Asn}$ and Asp-tRNA$^{Asp}$. Plus primary sequence distinguishes two general groups of AspRS. There is a predominantly bacterial-type, larger AspRS (about 580 aa) in addition to a shorter archaeal/eukaryotic type (about 430 aa). In vivo data made clear that discriminating and non-discriminating enzymes exist in both groups. The determinants in the protein sequence responsible for tRNA discrimination are not hewn. The AspRS from Acidithiobacillus ferrooxidans might be suggested ND-AspRS fur missing of AsnRS in genomic sequencing data. Therefore, we analyzed the AspRS from A. ferrooxidans with in vitro aminoacylation assay with E. coli unfractionated tRNA, in vivo missense suppression assay with tipA34 mutant and Northern hybridization with probes which were specific with tRNA$^{Asp}$ or tRNA$^{Asn}$. The AspRS from A. ferrooxidans produced more Asp-tRNA than that from E. coli. Only aspS gene from A. ferrooxidans suppressed trpA34 strain in minimal media without tryptophan. Only AspRS from A. ferrooxidans showed mischarged Asp-tRNA$^{Asn}$ band. Therefore, AspRS from A. ferrooxidans is definitely ND-AspRS.

• Asian Pacific Journal of Cancer Prevention
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• 제16권5호
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• pp.1977-1980
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• 2015

Objective: The Von Hippel-Lindau syndrome (VHLD), an inherited neoplastic syndrome predisposing to central nervous system hemangioblastoma (CNS), pheochromocytoma (PCC), renal cell carcinoma(RCC), retinal hemangioma (RA) and renal cysts, is caused by mutations or deletions of the VHL tumor-suppressor gene. To assess VHL genotype-phenotype correlations with function of pVHL a gene mutation analysis of members in a Chinese family with non-syndromic PCCs and individuals with apparently sporadic pheochromocytoma (ASP) was performed. Materials and Methods: DNA samples of 20 members from the Chinese family with non-syndromic PCCs and 41 patients with ASP were analyzed by polymerase chain reaction and direct sequencing, confirmed by Taqman probe. Results: Three novel mutations (H125P, 623(^TTTGTtG) and R120T) were identified in the Chinese family and in 3 among 41 ASP patients. The mutations were all located in exon 2 of VHL gene encoding ${\beta}$-domain of pVHL. The tumor type in H125P carriers and R120T carriers was VHL type 2C. And 623(^TTTGTtG) carriers presented VHL type 2B or type 2C. Conclusions: VHL gene abnormalities were identified in the Chinese family with non-syndromic PCCs and patients with APS, resulting in dysfunction of pVHL. H125P and R120T could be associated with VHL type 2C, while 623(^TTTGTtG) might be linked with VHL type 2B or type 2C. Not only is the genetic analysis helpful for early diagnosis and treatment of patients with VHLD, it is also benefitial for research intoVHLD pathogenesis.

• Journal of Animal Science and Technology
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• 제54권1호
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• pp.1-8
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• 2012

본 연구는 한국재래돼지의 MC4R 유전자 내의 단일염기변이들을 규명하고 그 유전자형 효과가 유전자표지인자를 이용한 선발(Marker assisted selection, MAS)에 활용 가능한지를 검증하기 위해서 수행되었다. 한국재래돼지의 MC4R 유전자 총 염기서열을 분석하기 위해 6개의 Primer들을 이용하여 증폭산물을 생성하였으며, 염기서열분석을 통해 총 6개(c.-780C>G, c-135C>T, c.175C>T-Leu59Leu, c.707A>G-Arg236His, c.892A>G-Asp298Asn, c.*430A>T)의 단일염기변이를 발견하였다. 한국재래돼지 MC4R 유전자내의 총 6개의 단일염기변이들간의 연관불균형과 반수체 분석을 통해 단일염기변이들간의 연관성을 분석하였으며, c.-780C>G, c-135C>T, c.175C>T-Leu59Leu, c.707A>G-Arg236His와 c.*430A>T는 완전한 연관불균형을 이루고 있었고, c.892A>G(Asp298Asn) 단일염기변이만 $r^2$-value가 0.028, D'-value가 0.348로 연관불균형 정도가 매우 낮았다. c.707A>G (Arg236His)와 c.892A>G (Asp298Asn) 단일염기변이들을 선발하여 PCR-RFLP 유전자형 분석방법을 이용해 돼지 5품종간의 유전자형 빈도를 추정한 결과, c.707A>G (Arg236His) 단일염기변이는 요크셔 품종 집단에서 오직 A (His) 대립유전자를 관찰할 수 있었으며, 나머지 한국재래돼지, 랜드레이스, 버크셔와 듀록 품종에서는 G 대립유전자의 고정으로 나타났다. c.707A>G 단일염기변이와 육질형질을 484두에서 연관성 분석을 실시한 결과, 조지방, 등심 내의 수분, 육색, 적색도 그리고 황색도 등에서 유의적인 연관성을 관찰할 수 있었다. c.892A>G (Asp298Asn) 단일염기변이의 유전자형 빈도는 품종별로 차이가 났으며, A (Asn) 대립유전자의 빈도가 가장 높은 품종은 듀록으로 나타났고, G (Asp) 대립유전자의 빈도가 가장 높은 품종은 한국재래돼지로 조사되었다. c.892A>G (Asp 298Asn) 단일염기변이와 돼지 4 집단의 육질형질을 1,126두에서 분석한 결과, 등지방두께에 고도의 유의적인 효과를 관찰할 수 있었다(P<0.002). AA 유전자형을 가진 개체가 AG나 GG 유전자형을 가진 개체보다 등지방두께가 두꺼운 것을 확인할 수 있었다. 본 연구의 결과를 통해 MC4R 유전자 내의 c.892A>G (Asp298Asn) 단일염기변이는 돼지의 선발개량에 유전자표지인자로서 충분한 효과가 있음을 검증하였다.

• Genomics & Informatics
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• 제8권2호
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• pp.70-75
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• 2010

Asp66his, Asp54Lys, and Asp50Asn are mutations in connexin 26 that are observed in the clinic and give rise to autosomal dominant syndromes. They are the result of point mutations in the human gap junction ${\beta}-2$ gene. In order to investigate the structural mechanism of Bart-Pumphrey Syndrome, Keratitis-Ichthyosis-Deafness Syndrome, and Vohwinkel Syndrome, homology modeling was carried out. Asp66 has direct contact with Asn62 by two hydrogen bonds in the wild-type protein, and in Asp66His, the biggest change observed is a tremendous energy increase caused by hydrogen bond breakage to Asn62. Shifts in the side chain and new hydrogen bond formation are observed for Lys54 compared to the wild-type protein (Asn54) and result in closer contact to Val84. Asp50Asn causes a significant decrease in bond energy, and residual charge reversal repels the ion and metabolites and, hence, inhibits their transportation. Such perturbations are likely to be a factor contributing to abnormal functioning of ion channels, resulting cell death and disease.

• 한국동물위생학회지
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• 제42권3호
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• pp.153-159
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• 2019

The objective of this study was to identify mutations in the quinolone resistance determining region (QRDR) of the gyrA, gyrB, parC and parE genes, and the presence of plasmid-mediated quinolone resistance (PMQR) genes: qnrA, qnrB, qnrS, aac(6')-lb-cr and qepA in 40 nalidixic acid- resistant ($NA^R$) Salmonella isolates isolated from poultry slaughterhouse. The MIC of NA and ciprofloxacin for 40 $NA^R$ Salmonella isolates was $128{\sim}512{\mu}g/mL$ and < $0.125{\sim}0.25{\mu}g/mL$, respectively. The Salmonella isolates were resistant to NA (100%), gentamicin (5.0%) and ampicillin (2.5%). All $NA^R$ Salmonella isolates represented point mutation in codons Aspartic acid(Asp)-87 (90%) and Serine(Ser)-83 (10%) of QRDR of gyrA gene: $Asp87{\rightarrow}glycine$, $Ser83{\rightarrow}tyrosine$. No mutations were observed in QRDR of the gyrB, parC and parE gene. Moreover PMQR genes was not found in any of the tested isolates. Our findings showed that DNA gyrase is the primary target of quinolone resistance and a single mutation in codon Asp87 and Ser83 of the gyrA gene can confer resistance to NA and reduced susceptibility ciprofloxacin in Salmonella isolates.

• Asian Pacific Journal of Cancer Prevention
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• 제14권2호
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• pp.665-668
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• 2013

Endothelial nitric oxide synthase (eNOS), encoded by the NOS3 gene, has been suggested to play an important role in uncontrolled cell growth in several cancer types. The objective of this study was to evaluate the role of the NOS3 Glu298Asp polymorphism in bladder cancer susceptibility in a Turkish population. We determined the genotypes of 66 bladder cancer cases and 88 healthy controls. Genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism analysis. A significant association for NOS3 Glu298Asp heterozygotes genotypes and T allele were found between healthy controls and bladder cancer, respectively (p<0.001: p=0.002). There were no significant associations between any genotypes and the stage, grade, and histological type of bladder cancer. Our study suggested an increased risk role of NOS3 GT genotype in bladder cancer susceptibility in our Turkish population.

• Journal of Microbiology and Biotechnology
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• 제25권10호
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• pp.1648-1652
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• 2015

Azaphilone polyketides are synthesized by iterative non-reducing fungal polyketide synthases (NR-fPKSs) with a C-terminus reductive domain (-R). Several azaphilone biosynthetic gene clusters contain a putative serine hydrolase gene; the Monascus azaphilone pigment (MAzP) gene cluster harbors mppD. The MAzP productivity was significantly reduced by a knockout of mppD, and the MAzP NR-fPKS-R gene (MpPKS5) generated its product in yeast only when co-expressed with mppD. Site-directed mutations of mppD for conserved Ser/Asp/His residues abolished the product formation from the MpPKS5/mppD co-expression. MppD and its homologs are thus proposed as a new protein factor involved in the product formation of NR-fPKS-R.

• Journal of Microbiology and Biotechnology
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• 제2권1호
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• pp.1-6
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• 1992

The aspartame, $\alpha$-L-aspartyl-L-phenylalanine methylester, is an artificial sweetener. Taking advantage of the fact that the aspartame is a derivative of dipeptide, synthesis of aspartame from the artificial polypeptide made by an artificial gene has been attempted. The artificial polypeptide (LAP32), a polymer of tripeptide (aspartyl-phenylalanyl-lysine), was purified from the E. coli cells harboring a recombinant plasmid containing the artificial gene. This polypeptide was then digested with trypsin and carboxypeptidase B to produce dipeptide (Asp-Phe). Using the esterase activity of $\alpha$-chymotrypsin, the dipeptide was directly converted into Asp-Phe methylester in a water-methanol system. When the methanol concentration in reaction mixture was 25%, 50% of dipeptide was converted to the dipeptide methylester without producing any by-products.

• Molecules and Cells
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• 제23권3호
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• pp.280-286
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• 2007

L-asparaginase (EC 3.5.1.1) catalyzes the hydrolysis of the amide group of L-asparagine, releasing aspartate and $NH_4{^+}$. We isolated a low temperature-inducible cDNA sequence encoding L-asparaginase from soybean leaves. The full-length L-asparaginase cDNA, designated GmASP1, contains an open reading frame of 1,258 bp coding for a protein of 326 amino acids. Genomic DNA blotting and fluorescence in situ hybridization showed that the soybean genome has two copies of GmASP1. GmASP1 mRNA was induced by low temperature, ABA and NaCl, but not by heat shock or drought stress. E. coli cells expressing recombinant GmASP1 had 3-fold increased L-asparaginase activity. A possible function of L-asparaginase in the early response to low temperature stress is discussed.