• BMB Reports
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• v.37 no.2
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• pp.192-198
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• 2004

The hepatitis C virus (HCV) core protein is believed to be one of viral proteins that are capable of preventing virus-infected cell death upon various stimuli. But, the effect of the HCV core protein on apoptosis that is induced by various stimuli is contradictory. We examined the possibility that the HCV core protein affects the ceramide-induced cell death in cells expressing the HCV core protein through the sphingomyelin pathway. Cell death that is induced by $C^2$-ceramide and bacterial sphingomyelinase was analyzed in 293 cells that constitutively expressed the HCV core protein and compared with 293 cells that were stably transfected only with the expression vector. The HCV core protein inhibited the cell death that was induced by these reagents. The protective effects of the HCV core protein on ceramide-induced cell death were reflected by the reduced expression of $p21^{WAF1/Cip1/Sid1}$ and the sustained expression of the Bcl-2 protein in the HCV core-expressing cells with respect to the vector-transfected cells. These results suggest that the HCV core protein in 293 cells plays a role in the modulation of the apoptotic response that is induced by ceramide. Also, the ability of the HCV core protein to suppress apoptosis might have important implications in understanding the pathogenesis of the HCV infection.

• Genomics & Informatics
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• v.18 no.3
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• pp.28.1-28.9
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• 2020

Streptomyces coelicolor is a gram-positive soil bacterium which is well known for the production of several antibiotics used in various biotechnological applications. But numerous proteins from its genome are considered hypothetical proteins. Therefore, the present study aimed to reveal the functions of a hypothetical protein from the genome of S. coelicolor. Several bioinformatics tools were employed to predict the structure and function of this protein. Sequence similarity was searched through the available bioinformatics databases to find out the homologous protein. The secondary and tertiary structure were predicted and further validated with quality assessment tools. Furthermore, the active site and the interacting proteins were also explored with the utilization of CASTp and STRING server. The hypothetical protein showed the important biological activity having with two functional domain including POD-like_MBL-fold and rhodanese homology domain. The functional annotation exposed that the selected hypothetical protein could show the hydrolase activity. Furthermore, protein-protein interactions of selected hypothetical protein revealed several functional partners those have the significant role for the bacterial survival. At last, the current study depicts that the annotated hypothetical protein is linked with hydrolase activity which might be of great interest to the further research in bacterial genetics.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.12
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• pp.3011-3016
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• 2015

Representing protein three-dimensional structure by concatenating a sequence of protein fragments gives an efficient application in analysis, modeling, search, and prediction of protein structures. This paper investigated the effective combination of distance measures, which can exploit large protein structure database, in order to construct a protein fragment library representing native protein structures accurately. Clustering method was used to construct a protein fragment library. Initial clustering stage used inter alpha-carbon distance having low time complexity, and cluster extension stage used the combination of inter alpha-carbon distance, Binet-Cauchy distance, and root mean square deviation. Protein fragment library was constructed by leveraging large protein structure database using the proposed combination of distance measures. This library gives low root mean square deviation in the experiments representing protein structures with protein fragments.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.6
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• pp.460-464
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• 2000

Extracellular polymeric substances (EPS) are believed to play a role in the binding and formation of microbial flocs. However, the precise role is not well known. Sludge settling characteristics and the carbohydrate to protein ratio in EPS were tested with various airflow rates in this study. Sludge was collected from three modified sequencing batch reactors (SBRs), which were operated at 16$\^{C}$ with an airflow rate of 0.8L/min, 3L/min and 6L/min, respectively. During the operation, the reactor operated at an airflow rate of 0.8L/min showed sludge volume index (SVI) of 80 to 90ml/g and a constant ratio of carbohydrate to protein in the EPS, while a significant increase in the SVI was seen in the other reactors. Sludge bulking increased the amount of carbohydrate in the EPS, while kept protein almost constant in the airflow rate of 3L/min ad 6L/min. Surface charge also increased with increases in the carbohydrate to protein ratio in the EPS, which weakens the attraction between the EPS and multivalent cations. The ratio of carbohydrate to protein in the EPS was tween the EPS and multivalent cations. The ratio of carbohydrate to protein in the EPS was inferred to be essential for bioflocculation.

• Journal of Microbiology and Biotechnology
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• v.6 no.6
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• pp.451-455
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• 1996

Physiological studies on the expression of Bacillus thuringiensis subsp. tenebrionis (Btt) gene coding for insecticidal protein in recombinant Escherichia coli 537 were carried out to identify optimal culture condition. It was necessary to shift culture temperature from 30 to $42^{\circ}C$ to express the gene. Expression of the Btt toxin gene by recombinant E. coli 537 began within one hour after induction. Complex nitrogen sources increased production of the insecticidal protein. The total insecticidal protein was 0.5 g/I when using yeast extract as a complex nitrogen source. Soybean hydrolysate showed apparently the highest induction efficiency. After induction, the cellular content of the insecticidal protein was 5.4 times higher than it had been before induction. The optimal cultivation strategy was found to grow cells for 7hours at $30^{\circ}C$ and then 5-8 hours at $42^{\circ}C$. The optimal cultivation pH for the production of insecticidal protein was 6.5. The Btt toxin produced by the recombinant E. coli 537 was found to have the same level of potency against Colorado potato beetle as the original toxin.

• Applied Chemistry for Engineering
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• v.9 no.2
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• pp.311-316
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• 1998

The adsorption equilibrium properties of bovine serum albumin(BSA-protein) for three kinds of porous microgels with different physical and chemical features were investigated. The adsorption amount of BSA-protein on poly(butyl methacrylate)(PBMA) microgels was higher than those on poly(vinyl pyridine)(PVP) and poly(acrylonitrile) (PAN) microgels due to the hydrophobic interaction between polymer and protein in an aqueous solution. And PBMA microgels had more irreversible adsorption equilibrium properties the PVP and PAN microgels. It implies that hydrophobic interaction plays a more important role in adsorption properties of BAS-protein than physical properties of polymer and electrostatic attraction between protein and polymer microgels. Characteristics of the microgels used in this study followed Langmuir equation better than the Freundlich equation.

• Genomics & Informatics
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• v.20 no.1
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• pp.6.1-6.15
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• 2022

Litorilituus sediminis is a Gram-negative, aerobic, novel bacterium under the family of Colwelliaceae, has a stunning hypothetical protein containing domain called von Hippel-Lindau that has significant tumor suppressor activity. Therefore, this study was designed to elucidate the structure and function of the biologically important hypothetical protein EMK97_00595 (QBG34344.1) using several bioinformatics tools. The functional annotation exposed that the hypothetical protein is an extracellular secretory soluble signal peptide and contains the von Hippel-Lindau (VHL; VHL beta) domain that has a significant role in tumor suppression. This domain is conserved throughout evolution, as its homologs are available in various types of the organism like mammals, insects, and nematode. The gene product of VHL has a critical regulatory activity in the ubiquitous oxygen-sensing pathway. This domain has a significant role in inhibiting cell proliferation, angiogenesis progression, kidney cancer, breast cancer, and colon cancer. At last, the current study depicts that the annotated hypothetical protein is linked with tumor suppressor activity which might be of great interest to future research in the higher organism.

• Korean Journal of Pharmacognosy
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• v.23 no.3
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• pp.142-145
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• 1992

MeOH extract of twenty medicinal herbs were screened for their effects against protein kinase C (PKC) using bleb-forming assay and PKC enzyme assay. Smilax china and Sanguisorba officinalis showed potent anti-PKC activity. Campsis grandiflora and Galla Halepensis showed moderate inhibitory effect on PKC.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.3
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• pp.268-272
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• 2006

A dense, pellicular UpFront adsorbent ($p=1.5 g/cm^3$, UpFront Chromatography, Cophenhagen, Denmark) was characterized in terms of hydrodynamic properties and protein adsorption performance in expanded bed chromatography. Cibacron Blue 3GA was immobilised into the adsorbent and protein adsorption of bovine serum albumin (BSA) was selected to test the setup. The Bodenstein number and axial dispersion coefficient estimated for this dense pellicular adsorbent was 54 and $1.63{\times}10^{-5}m^2/s$, respectively, indicating a stable expanded bed. It could be shown that the BSA protein was captured by the adsorbent in the presence of 30% (w/v) of whole-yeast cells with an estimated dynamic binding capacity $(C/C_o = 0.01)$ of approximately 6.5 mg/mL adsorbent.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.408-411
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• 2005

The green fluorescent protein (GFP) from the jellyfish aequorea and its fluorescent homologs from Anthozoa corals have become invaluable tools for imaging of cells and tissues. In this study various fluorescent protein such as green fluorescent protein (GFP), yellow fluorescent protein (YFP) and red fluorescent protein (RFP) have been expressed in Escherichia coli. Growth of recombinant cells and production of fluorescent proteins were investigated in shake flasks. Some characteristics of fluorescent proteins was also studied.