• Biomedical Science Letters
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• v.11 no.1
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• pp.85-88
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• 2005

Hemoglobin is oxygen carrier protein within erythrocyte in blood. Apoprotein of this, globin, is synthesized in the cytosol but it's cofactor, heme, is synthesized in the mitochondria. It has not been known very well how globin receives the heme from mitochondria and folds to hemoglobin. In this folding process, the initial structure of globin seems to be very important. A small volume of globin at acid pH was added rapidly into the bulk of an egg phosphatidylcholine $60\%$ liposome, containing hemins, at neutral pH according to the Rapid Dilution method. It was observed that an acid-induced unfolding structure of globin is initially needed to receive hemins from the lipid bilayer of liposomes. Also, this conclusion was confirmed with the absorption spectrum of the refolded globin separated by centrifugation.

• Journal of Microbiology and Biotechnology
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• v.24 no.10
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• pp.1405-1412
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• 2014

Lysozyme is a protein found in egg white, tears, saliva, and other secretions. As a marketable natural alternative to preservatives, lysozyme can act as a natural antibiotic. In this study, we have isolated Bacillus licheniformis TIB320 from soil, which contains a lysozyme gene with various features. We have cloned and expressed the lysozyme in E. coli. The antimicrobial activity of the lysozyme showed that it had a broad antimicrobial spectrum against several standard strains. The lysozyme could maintain efficient activities in a pH range between 3 and 9 and from $20^{\circ}C$ to $60^{\circ}C$, respectively. The lysozyme was resistant to pepsin and trypsin to some extent at $40^{\circ}C$. Production of the lysozyme was optimized by using various expression strategies in B. subtilis WB800. The lysozyme from B. licheniformis TIB320 will be promising as a food or feed additive.

• Macromolecular Research
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• v.17 no.7
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• pp.464-468
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• 2009

Gelatin nanoparticles derived from bovine or porcine have been developed as various types of drug delivery system, and they need to be cross-linked to maintain their physicochemical properties in aqueous environments. Although gelatin is a widely used material in pharmaceutical industries, the safety issue of animal-origin gelatins, such as transmissible mad cow disease and anaphylaxis, remains to be solved. The purpose of this study was to prepare type A gelatin (GA) nanoparticles by modified, two-step, desolvation method and compare the toxicity of the resulting GA nanoparticles with recombinant human gelatin (rHG) nanoparticles. The GA nanoparticles were characterized, and drug loading and release pattern were measured. FITC-BSA, a model protein, was efficiently loaded in the nanoparticles and then released in a biphasic and sustained release pattern without an initial burst. In particular, the cell viability of the GA nanoparticles was less than that of the rHG nanoparticles. This finding suggests that rHG nanoparticles should be considered as an alternative to animal-origin gelatin nanoparticles in order to minimize the safety problems.

• Tuberculosis and Respiratory Diseases
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• v.75 no.5
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• pp.188-198
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• 2013

Over the past decade, several kinase inhibitors have been approved based on their clinical benefit in cancer patients. Unfortunately, in many cases, patients develop resistance to these agents via secondary mutations and alternative mechanisms. To date, several major mechanisms of acquired resistance, such as secondary mutation of the epidermal growth factor receptor (EGFR) gene, amplification of the MET gene and overexpression of hepatocyte growth factor, have been reported. This review describes the recent findings on the mechanisms of primary and acquired resistance to EGFR tyrosine kinase inhibitors and acquired resistance to anaplastic lymphoma kinase inhibitors, primarily focusing on non-small cell lung carcinoma.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.6
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• pp.395-401
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• 2001

Crystallins are a family of water-soluble proteins that constitute up to 90% of the wa-ter-soluble proteins in mammalian eye lenses, We present in this paper an alternative purification method for these proteins using polyethylene glycol/dextran aqueous two-phase extraction. Un-der the appropriate conditions, we were able to recover the γ-crystallin fraction essentially free of the remaining proteins. High concentrations of salt at a neutral pH maximize the recovery of γ-crystallins in the top phase and minimize the contamination by the other proteins present in the lenses. The proposed protocol decreases the separation time by about 50%. The complex partition behavior observed for these proteins reflects a delicate balance between protein/phase-forming species(various polymers and salts) and protein interactions. This is evidenced, in part, by the role played by the largest proteins in this group as a "pseudo"phase-forming species.

• Natural Product Sciences
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• v.13 no.4
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• pp.328-331
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• 2007

The methanolic extract of the roots of Lithospermum erythrorhizon (Boraginaceae) was found to show inhibitory activity towards farnesyl protein transferase (FPTase). Bioassay-guided fractionation of the methanolic extract resulted in the isolation of three naphthoquinone compounds, as inhibitors of FPTase. These compounds inhibited the FPTase activity in a dose-dependent manner.

• Microbiology and Biotechnology Letters
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• v.50 no.2
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• pp.240-244
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• 2022

Precisely reliable and quantitative reporters can provide phenotypes that are consistent with research goals in protein expression. Here, we developed an improved reporter mATglu III 5 by directed evolution using a versatile β-glucosidase ATglu derived from Agrobacterium tumefaciens. When expressed in hosts, a vector containing this mutant distinctly showed a colored or fluorescent phenotype, according to the supplemented substrate, without any inducer. Analysis of mATglu III 5 showed it to be fully functional in fusion state with oligomeric proteins, especially under non-induction conditions, thereby offering an alternative to conventional reporters.

• 순환기질환의공학회:학술대회논문집
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• 2006.10a
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• pp.10-13
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• 2006

Inflammation plays an important role in the progression of atherosclerosis and plaque destabilization converting a chronic process into an acute disorder with ensuing thromboembolism. Current therapeutic effective in preventing atherosclerosis and stroke such as statins, ASS and RAS inhibitors my exert part of their effects by modulating inflammatory responses in the vessel walls. As alternative approaches, discovery to find having inhibitory action of MMP activity, COX-2, macrophage infiltration, such as APE1/ref-1 and fusion technology for cell permeable protein may provide a new antiatherosclerotic therapy in the future.

• BMB Reports
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• v.32 no.5
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• pp.497-501
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• 1999

Biotinylation of recombinant proteins is a powerful tool for the detection and analysis of proteins of interest in a large variety of assay systems. The recent development of in vivo biotinylation techniques in E. coli has opened new possibilities for the production of site-specifically biotinylated proteins without the need for further manipulation after the isolation of the recombinantly expressed proteins. In the present study, a novel vector set was generated which allows the convenient cloning and expression of proteins of interest fused with an N-terminal in vivo biotinylated thioredoxin (TRX) protein. These vectors were derived from the previously reported pBIOTRX vector into which was incorporated part of the pBluescript II+phagemid multiple cloning site (MCS), amplified by PCR using a pair of sophisticated oligonucleotide primers. The functionality of these novel vectors was examined in this system by recombinant expression of rat transforming growth factor-$\beta$. Western-blot analysis using TRX-specific antibodies or peroxidase-conjugated streptavidin confirmed the successful induction of the fusion protein and the in vivo conjugation of biotin molecules, respectively. The convenience of molecular subcloning provided by the MCS and the effective in vivo biotinylation of proteins of interest makes this novel vector set an interesting alternative for the production of biotinylated proteins.

• Fisheries and Aquatic Sciences
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• v.5 no.3
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• pp.172-177
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• 2002

This study was conducted to investigate the utilization of Sargassum meal in the diet on juvenile ayu (Plecoglossus altivelis) reared in seawater. White fish meal and wheat flour were used as the dietary protein and carbohydrate sources in the control diet. Wheat flour in the control diet was replaced with $5\%$ and $10\%$ Sargassum meal. Three replicate groups of fish average weighing 4.0 g were fed one of three isonitrogenous$(45\%)$ and isocaloric (14.5 MJ /kg diet) diets for 7 weeks. Survival of all groups were above $80\%$. Weight gain, feed efficiency and protein efficiency ratio were not significantly affected by dietary Sargassum meal levels (P>0.05). There were no significant differences (P>0.05) in moisture, crude protein, crude lipid, crude ash and fatty acid compositions of whole-body fish among groups. It is concluded that Sargassum meal could be used as a dietary additive or alternative low-cost dietary ingredient up to $10\%$ for juvenile ayu reared in seawater.