• Journal of Microbiology
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• 제39권1호
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• pp.31-36
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• 2001

A cDNA clone encoding the ribosomal protein S20 has been isolated from the Schizosaccharomyces pombe cDNA library by colony hybridization. The insert contained in the original plasmid pYJ10 was transferred intro shuttle vector pRS316 generate plasmid pYJll. The dDNA insert of plasmid pYJll, contains 484 nucleotides and encodes a protein of 118 amino acids with a calculated mass of 13,544 daltons. The deduced amino acid sequence of S. pombe ribosomal protein S20 is very homologous with fruit fly, rat, and budding yeast counterparts. It is also homologous with Xenopus S22 ribosomal protein. S. pombe ribosomal protein S20 appears to be relatively hydruphobic except the C-terminal region. The 728 bp upstream region of the S20 gene was amplified from chromosomal DNA and transferred into the BamHI/EcoRI site of the promoterles $\beta$-galactosidase gene of the vector YEp357R, which resulted in fusion plasmid pYS20. The synthesis of $\beta$-galactosidase from the fusion plasmid appeared to be the highest in the mid-exponential phase. The S. pombe cells with the fusion plasmid grown at 35$\^{C}$ gave lower $\beta$-galactosidase activity than the cells grown at 30$\^{C}$. Computer analysis showed the consensus sequence CAGTCACA in the upstream regions of various ribosomal protein genes in S. pombe, which would be involved in the coordinated expression of small ribosomal proteins.

• Macromolecular Research
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• 제11권1호
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• pp.53-61
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• 2003

A molecular-thermodynamic model is developed for the salt-induced protein precipitation. The protein molecules interact through four intermolecular potentials. An equation of state is derived based on the statistical mechanical perturbation theory with the modified Chiew's equation for the fluid phase, Young's equation for the solid phase as the reference system and a perturbation based on the protein-protein effective two body potential. The equation of state provides an expression for the chemical potential of the protein. In a single protein system, the phase separation is represented by fluid-fluid equilibria. The precipitation behaviors are simulated with the partition coefficient at various salt concentrations and degree of pre-aggregation effect for the protein particles. In a binary protein system, we regard the system as a fluid-solid phase equilibrium. At equilibrium, we compute the reduced osmotic pressure-composition diagram in the diverse protein size difference and salt concentrations.

• Bulletin of the Korean Chemical Society
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• 제28권10호
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• pp.1756-1762
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• 2007

Envelope proteins of virus contain a segment of hydrophobic amino acids, called as fusion peptide, which triggers membrane fusion by insertion into membrane and perturbation of lipid bilayer structure. Potential fusion peptide sequences have been identified in the middle of L or M proteins or at the N-terminus of S protein in the envelope of human hepatitis B virus (HBV). Two 16-mer peptides representing the N-terminal fusion peptide of the S protein and the internal fusion peptide in L protein were synthesized, and their membrane disrupting activities were characterized. The internal fusion peptide in L protein showed higher activity of liposome leakage and hemolysis of human red blood cells than the N-terminal fusion peptide of S protein. Also, the membrane disrupting activity of the extracellular domain of L protein significantly increased when the internal fusion peptide region was exposed to N-terminus by the treatment of V8 protease. These results indicate that the internal fusion peptide region of L protein could activate membrane fusion when it is exposed by proteolysis.

• Biomolecules & Therapeutics
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• 제26권6호
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• pp.533-538
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• 2018

Nitric oxide (NO) mediates various physiological and pathological processes, including cell proliferation, differentiation, and inflammation. Protein S-nitrosylation (SNO), a NO-mediated reversible protein modification, leads to changes in the activity and function of target proteins. Recent findings on protein-protein transnitrosylation reactions (transfer of an NO group from one protein to another) have unveiled the mechanism of NO modulation of specific signaling pathways. The intracellular level of S-nitrosoglutathione (GSNO), a major reactive NO species, is controlled by GSNO reductase (GSNOR), a major regulator of NO/SNO signaling. Increasing number of GSNOR-related studies have shown the important role that denitrosylation plays in cellular NO/SNO homeostasis and human pathophysiology. This review introduces recent evidence of GSNO-mediated NO/SNO signaling depending on GSNOR expression or activity. In addition, the applicability of GSNOR as a target for drug therapy will be discussed in this review.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2005년도 BIOINFO 2005
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• pp.388-391
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• 2005

The Protein Structural and Functional Conservation need a common language for data definition. With the help of common language provided by Protein Ontology the high level of sequence and functional conservation can be extended to all organisms with the likelihood that proteins that carry out core biological processes will again be probable orthologues. The structural and functional conservation in these proteins presents both opportunities and challenges. The main opportunity lies in the possibility of automated transfer of protein data annotations from experimentally traceable model organisms to a less traceable organism based on protein sequence similarity. Such information can be used to improve human health or agriculture. The challenge lies in using a common language to transfer protein data annotations among different species of organisms. First step in achieving this huge challenge is producing a structured, precisely defined common vocabulary using Protein Ontology. The Protein Ontology described in this paper covers the sequence, structure and biological roles of Protein Complexes in any organism.

• EDISON SW 활용 경진대회 논문집
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• 제3회(2014년)
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• pp.103-113
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• 2014

Hydrophobicity is the key concept to understand the role of water in protein folding, protein self-assembly, and protein-ligand interaction. Conventionally, hydrophobicity of amino acids in a protein has been argued based on hydrophobicity scales determined for individual free amino acids, assuming that those scales are unaltered when amino acids are embedded in a protein. Here, we investigate how the hydrophobicity of constituent amino acids depends on the protein context, in particular, on the total charge and secondary structures of a protein. To this end, we compute and analyze the hydration free energy - free energy change upon hydration quantifying the hydrophobicity - of three short proteins based on the integral-equation theory of liquids. We find that the hydration free energy of charged amino acids is significantly affected by the protein total charge and exhibits contrasting behavior depending on the protein net charge being positive or negative. We also observe that amino acids in the central ${\beta}$-strand sandwiched by ${\beta}$-sheets display more enhanced hydrophobicity than free amino acids, whereas those in the ${\alpha}$-helix do not clearly show such a tendency. Our results provide novel insights into the hydrophobicity of amino acids, and will be valuable for rationalizing and predicting the strength of water-mediated interaction involved in the biological activity of proteins.

• Plant Resources
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• 제8권2호
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• pp.110-115
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• 2005

Ribosomal protein complex with ribosomal RNA to form the subunits of the ribosome serve essential functions in protein synthesis. A full-length cDNA (PRPS4) encoding ribosomal protein S4 has been isolated and its nucleotide sequence determined in ginseng plant (Panax ginseng). A PRPS4 cDNA is 1105 nucleotides long and has an open reading frame of 792 bp with a deduced amino acid sequence of 264 residues (pI 10.67). The deduced amino acid sequence of PRPS4 matched to the previously reported ribosomal protein S4 genes. Their degree of amino acid identity ranged from 68 to $92\%$. Phylogenetic analysis based on the amino acid residues showed that the PRPS4 grouped with ribosomal protein S4 of S. tuberosum (CAA54095).

• 동아시아식생활학회지
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• 제5권3호
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• pp.385-394
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• 1995

Our previous reports on the effect of dietary protein on methanethiol, ethacrynic acid, bromobenzene and carbon tetrachloride metabolism were overall reviewed. The methanethiol, ethacrynicacid and bromobenzene treated rats showed the more severe liver damage in those fed a low protein diet than those fed a standard protein diet. These xenobiotics treated rats showed the lower content of hepatic glutathione and its conjugated enzyme, glutathione S-transferase activities in those fed a low protein diet than those fed a standard protein diet. In case of carbon tetrachloride treated rats, the liver damage was more reduced in rats fed a low protein diet than those fed a standard protein diet. Concomitantly the hepatic cytochrome P-450 content, and its decreasing rate to the control were lower in rats fed a low protein diet than those fed a standard protein diet.

• 한국식품영양과학회지
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• 제22권1호
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• pp.15-18
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• 1993

식이성단백이 methanethiol에 의한 간기능에 어떠한 영향을 미치는지를 검토코자 흰쥐를 저단백식이(LP : casein 7%) 및 고단백식이 (HP : casein 20%)로 1개월간 성장시킨 뒤 methanethiol을 투여한 다음, 간무게, 혈청 ALT 활성을 측정하여 간기능 정도를 두 군간에 비교하였다. 동시에 이에 대한 원인을 규명하는 일환으로 간조직 중 glutahione함량과 glutathione 포함효소의 일종인 glutathione S-transferase (GST)활성을 측정하여 다음과 같은 실험 결과를 얻었다. Methanethiol 투여로 인한 대조군에 대한 간무게와 혈청 ALT활성 증가율은 LP군이 HP군보다 높았으며, 간 glutathione함량과 간 GST활성이 HP군 보다 LP군이 낮게 나타났다. 이상 성적을 종합해 볼 때 methanethiol에 의한 간 독성은 식이 중 단백함량감소에 비례해서 증가되며 이는 LP군이 HP군 보다 methanethiol해독에 관여하는 간 glutathione함량과 GST활성의 감소에 기인되기 때문인 것으로 생각된다.

• Journal of Nutrition and Health
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• 제32권8호
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• pp.855-863
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• 1999

This study was performed to investigate the effect of dietary protein level throughout gestation and lactation on milk composition and on postnatal growth in infants, using rats as an animal model. Female Sprague-Dawley rats were provided with either high(25% ISP(Isolated Soy Protein)diet) or low protein diet(10% ISP diet) throughout gestation and lactation. Milk samples were taken for analysis from the lactating rats at days of 7, 14, 21, of lactation. Dams and some pups were killed after 4 weeks from parturtion (Experiment 1). Pups from dams of each diet groups were randomly selected and reared with 25% or 10% ISP diet for 4 more weeks (Experiment 2). In experiment 1, maternal protein intake and body weight gain throughout gestation and lactation was higher in 25% ISP group. Serum protein, Ca, Fe, Zn, K concentrations were significantly higher in 25% ISP group. There was no difference in birth weight between two groups, however the mean body weight at 4 weeks postpartum were significantly higher in 25% ISP group. Serum profiles of pups at weaning were similar to that of dams. Milk compositions were changed during lactation processes and were affected by dietary protein level. Lactose and Ca, Cu, Fe concentrations in milk were higher in 25% ISP group, whereas, lipid, triglyceride were higher in 10% ISP group. In experiment 2, food intake was higher in milk were higher in 25% ISP group but was unaffected by pup's dietary protein level after weaning. The weights of liver and kidney were affected by maternal protein intake. The weight of intestine was affected by pup's dietary protein level after weaning. The weight of femur and scapula were affected by maternal protein intake. There were no differences between four groups in serum profiles. Therefore, as mentioned above, it seemed that the effect of maternal protein malnutrition to fetus was able to be overcome to some extent by high protein diet intake after weaning. In conclusion, 1) Dietary protein level throughout gestation and lactation affected both nutritional status of dams and pups and milk composition: 25% ISP groups supported better nutritional status than 10% ISP group 2) It seemed that effect of dietary protein level after weaning on pups was able to be overcome the influence of maternal diet in fetus to some extent.