• Bulletin of the Korean Chemical Society
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• v.30 no.7
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• pp.1437-1438
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• 2009

• Journal of Microbiology and Biotechnology
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• v.17 no.8
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• pp.1249-1253
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• 2007

A hyperthermostable endoglucanase from Pyrococcus horikoshii with the capability of hydrolyzing crystalline cellulose was analyzed. A protein engineering study was carried out to obtain a reduced-size mutant. Five amino acid residues at both the N- and C-terminus were found to be removable without any loss of activity or thermal stability. Site-directed mutagenesis was also performed on R102, N200, E201, H297, Y299, E342, and W377, residues possibly involved in the active center or in the recognition and binding of a cellulose substrate. The activity of the resulting mutants was considerably decreased, confirming that the mutated residues were all important for activity. A reduced-size enzyme, as active as the wild-type endoglucanase, was successfully obtained, plus the residues critical for its activity and specificity were confirmed. Consequently, an engineered enzyme with a reduced size was obtained, and the amino acids essential for activity were confirmed by site-directed mutagenesis and comparison with a known three-dimensional structure.

• KSBB Journal
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• v.8 no.4
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• pp.405-408
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• 1993

Absidia zychae NRIC 1199 produced two forms of carboxypeptidase(CPZ-1 and CPZ-2) which were distinguished in their isoelectric points but had almost identical properties(1). The amino acid sequences for the N-terminal of both enzymes were the same (Tyr-Thr-Ser-Pro-Lys-Leu-Xaa-Asp-Pro-Asp-Val) and any significant difference was not observed between amino acid compositions of the two enzymes. The ouchterlony double diffusion technique using antibody raised against the CPZ-2 protein demonstrated a good cross-reaction between CPZ-1 and CPZ-2 Genomic Southern analysis showed only one gene encoding CPZ in the genome of Absidia zychae. However, a significant difference between two enzymes was observed on peptide map using Staphylococcus aureus V8 protease, distinguishable only one band, indicating that multiple forms of CPZ are caused by post-translational modification, such as deamidation.

• Bulletin of the Korean Chemical Society
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• v.23 no.6
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• pp.851-856
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• 2002

The Reaction of S-methyl-S-cysteine(L-Smc) with racemic $s-cis-[Co(demba)Cl_2]-1$ (Hydmedba = $NN'-dimethylethylenediamine-NN'-di-\alpha-butyric$, acid) yields ${\Delta}$-s-cis-[Co(dmedba)(L-Smc)] 2 with N, O-chelation. Oxidation of sulfur of 2 with $H_2O_2$ in a 1 : 1 mole ratio gives ${\Delta}$-s-cis[Co(dmedba)(L-S(O)mc)] 3 having an uncoordinated sulfenate group. Oxidation of sulfur of L-Sm with $H_2O_2in$ a 1: 1 mole ratio produces S-methyl-L-cysteinesulfenate (L-S(O)me) 5. Direct reaction of 1 with 5 in basic medium gives an N.O-chelated ${\Delta}$s-cis[Co(dmedba)(L-S(O)mc)-N.O], which turmed out be same as obtained by oxidation of 2, while an N, S-chelated ${\Delta}$-s-cis-[Co(dmedba)(S-S(O)mc)-N,O] complex 4 is obtained in acidic medium from the reaction of 1 with 5. This is one of the rare $[$Co^{III}$(N_2O_2-type$ ligand)(amino acid)] type complex preparations, where the reaction conditions determine which mode of N, O and N, S caelation modes is favored.

• Bulletin of the Korean Chemical Society
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• v.30 no.3
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• pp.647-652
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• 2009

A novel spiro-type host material, 5-[4-(1-naphthyl)phenyl]-spiro[fluorene-7,9'-benzofluorene] (BH-1PN) and three new dopants, namely, 5-[diphenylamino)phenyl]-spiro[fluorene-7,9'-benzofluorene] (BH-1TPA), 5-[4-(N-phenyl (m-tolyl)amino]-spiro[fluorene-7,9'-benzofluorene] (BH-1MDPA) and 5-[(N-phenyl)-2-naphthyl]amino-spiro[fluorene- 7,9'-benzofluorene] (BH-1NPA) were designed and successfully prepared using the Suzuki or amination reactions. The electroluminescence characteristics of BH-1PN as a blue host material doped with each of the blue dopants were evaluated. The structure of the device is ITO/DNTPD/NPB/BH-1PN:5% dopant/Alq3/Al-LiF. The device obtained from BH-1PN doped with diphenyl-[4-(2-[1,1;4,1]terphenyl-4-yl-vinyl)phenyl]-amine (BD-1) showed good color purity, efficiency, luminance, and current-density characteristics.

• Archives of Pharmacal Research
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• v.21 no.6
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• pp.712-717
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• 1998

The complete nucleotide sequence of the cDNA clone encoding rat skeletal muscle myosin- binding protein H (MyBP-H) was determined and amino acid sequence was deduced from the nucleotide sequence (GenBank accession number AF077338). The full-length cDNA of 1782 base pairs(bp) contains a single open reading frame of 1454 bp encoding a rat MyBP-H protein of the predicted molecular mass 52.7kDa and includes the common consensus 1CA__TG' protein binding motif. The cDNA sequence of rat MyBP-H show 92%, 84% and 41% homology with those of mouse, human and chicken, respectively. The protein contains tandem internal motifs array (-FN III-Ig C2-FN III- Ig C2-) in the C-terminal region which resembles to the immunoglobulin superfamily C2 and fibronectin type III motifs. The amino acid sequence of the C-terminal Ig C2 was highly conserved among MyBPs family and other thick filament binding proteins, suggesting that the C-terminal Ig C2 might play an important role in its function. All proteins belonging to MyBP-H member contains `RKPS` sequence which is assumed to be cAMP- and cGMP-dependent protein kinase A phosphorylation site. Computer analysis of the primary sequence of rat MyBP-H predicted 11 protein kinase C (PKC)phosphorylation site, 7 casein kinase II (CK2) phosphorylation site and 4N-myristoylation site.

• Food Science and Preservation
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• v.17 no.4
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• pp.533-540
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• 2010

Overall composition, and fatty acid, amino acid, and nucleotide-type compound levels in wild (Haliotis gigantea) and cultured abalone (Haliotis discus hannai), were investigated. Wild abalone had a higher moisture content than did cultured abalone, but the converse was true for crude protein content. In overall composition, crude lipid level was higher in the viscera than in the meat, with the greatest level, $2.02{\pm}0.15%$ (w/w), observed in the viscera of wild abalone. The major fatty acids were palmitic acid (16:0), oleic acid (18:1n-9), eicosatrienoic acid (20:3n-3, ETA), eicosapentaenoic acid (20:5n-3, EPA), and docosahexaenoic acid (22:6n-3, DHA). The omega-3 fatty acid content (EPA and DHA) was higher in wild than in cultured abalone. A total of 17 amino acids were detected in all abalone samples, most of which had high levels of aspartic acid, glutamic acid, glycine, and arginine, and low amounts of cysteine, methionine, and histidine. Glutamic acid was the most abundant of all amino acids. The content of free amino acids was related to taste score. The major free amino acids were taurine, alanine, and arginine, of which taurine was the most abundant, and was present at higher levels in wild compared to cultured abalone. The total contents of nucleotide-related compounds in wild and cultured abalone were 12.93 mg/100g and 30.75 mg/100g, respectively.

• BMB Reports
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• v.43 no.6
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• pp.427-431
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• 2010

Cyt2Aa2 is a mosquito-larvicidal protein produced as a 29 kDa crystalline protoxin from Bacillus thuringiensis subsp. darmstadiensis. To become an active toxin, proteolytic processing is required to remove amino acids from its N- and C-termini. This study aims to investigate the functional role of amino acid residues on the N-terminal ${\beta}1$ and C-terminal ${\alpha}F$ of Cyt2Aa2 protoxin. Mutant protoxins were constructed, characterized and compared to the wild type Cyt2Aa2. Protein expression data and SDS-PAGE analysis revealed that substitution at leucine-33 (L33) of ${\beta}1$ has a critical effect on dimer formation and structural stability against proteases. In addition, amino acids N230 and I233-F237 around the C-terminus ${\alpha}F$ demonstrated a crucial role in protecting the protoxin from proteolytic digestion. These results suggested that ${\beta}1$ and ${\alpha}F$ on the Nand C-terminal ends of Cyt2Aa2 protoxin play an important role in the molecular interaction and in maintaining the structural stability of the protoxin.

• Applied Chemistry for Engineering
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• v.2 no.3
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• pp.216-221
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• 1991

Surface activities of four potassium N-acyl-N-methyl-${\beta}$-alaninate including surface tension, foaming power, foam stability, emulsifying power and dispersion power were measured respectively, and critical micelle concentration(cmc) was evaluated. Consequently these anionic surfactants with long chain acyl amide showed good emusifying power of O/W type, foaming, foam stability and dispersion effect.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.4
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• pp.403-409
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• 1995

A growth experiment was conducted to evaluate the nutritivie values of supplemental lysine and methionine in broiler chicks. Two types of L-lysine, liquid and powder type, and DL-methionine were added to the diets at different levels of dietary protein with two growth phases, 0-3 weeks and 4-6 weeks named starter and grower, respectively. Six hundred seventy two chicks were allotted in 14 treatments; 3 controls by dietary CP level (starter-grower) with CP 23-21%, CP 21-19% and CP 20-18, 8 groups of liquid and powder lysine supplementation of 0.1, 0.2, 0.3 and 0.4%, and 3 groups of lysine and methionine supplementation. Body weight, feed intake, and excreta were measured and analyzed to determine growth performance, amino acid digestibilities, and the quantity of excreted nitrogen in feces. Chicks fed CP 23-20 with 3,200 ME kcal showed significantly better growth performance than those fed CP 21-18 for 6 weeks. The supplementation of 0.2% of either type of lysine to CP 21-19 diet improved weight gain and feed efficiecy to the extent that CP 23-21 diet was fed. Physical type of lysine did not affect chick's growth and amino acid digestibilities of the diets. The level of CP in the diet significantly affected nitrogen excretion in feces. Supplementation of lysine and methionine to CP 21-18 diet reduced fecal nitrogen by 10% compared to CP 23-21 diet. It was confirmed that 0.2% of supplemental lysine to the broiler diet spared the dietary protein by 3%, and also reduced nitrogen excretion in feces by 10%.