• BMB Reports
• /
• 제29권2호
• /
• pp.175-179
• /
• 1996

Viral surface proteins are known to play an essential role in attachment of the virus particle to the host cell membrane. In case of the hepatitis B virus (HBV) several reports have described potential receptors on the target cell side, but no definite receptor protein has been isolated yet. As for the viral side, it has been suggested that the preS region of the envelope protein, especially the preS1 region, is involved in binding of HBV to the host cell. In this study, preS1 region was recombinantly expressed in the form of a maltose binding protein (MBP) fusion protein and used to identify and visualize the expression of putative HBV receptor(s) on the host cell. Using laser scanned confocal microscopy and by FACS analysis, MBP-preS1 proteins were shown to bind to the human hepatoma cell line HepG2 in a receptor-ligand specific manner. The binding kinetic of MBP-preS1 to its cellular receptor was shown to be temperature and time dependent. In cells permeabilized with Triton X-100 and treated with the fusion protein, a specific staining of the nuclear membrane could be observed. To determine the precise location of the receptor binding site within the preS1 region, several short overlapping peptides from this region were synthesized and used in a competition assay. In this way the receptor binding epitope in preS1 was revealed to be amino acid residues 27 to 51, which is in agreement with previous reports. These results confirm the significance of the preS1 region in virus attachment in general, and suggest an internalization pathway mediated by direct attachment of the viral particle to the target cell membrane.

• Asian-Australasian Journal of Animal Sciences
• /
• 제11권3호
• /
• pp.311-317
• /
• 1998

A total of 1033 Brown Swiss and 610 Canadienne cows were phenotyped for the genetic variants ${\alpha}_{s1}$-casein, ${\beta}$-casein, ${\kappa}$-casein, ${\beta}$-lactoglobulin and ${\alpha}$-lactalbumin. In Brown Swiss, frequency distributions were: 97.3% B and 2.7% C variant of ${\alpha}_{s1}$-casein; 31.6% $A^1$, 51.8% $A^2$, 0.5% $A^3$ and 16.1% B variant of ${\beta}$-casein; 70.4% A, 29.3% B, and 0.3% C variant of ${\kappa}$-casein; 41.7% A and 58.3% B variant of ${\beta}$-lactoglobulin; and 100% B variant of ${\alpha}$-lactalbumin. Corresponding frequencies in Canadienne for those five milk proteins were: 98.6 and 1.4%;58.5, 33.5, 0.08 and 7.9%; 78.8, 21.1 and 0.1%, 42.4 and 57.6%; and 100%. Analysis of variance by least squares showed possible association between milk protein phenotypes and some lactational production traits. There were no significant association of phenotypes of ${\alpha}_{s1}$-casein, ${\beta}$-casein and ${\beta}$-lactoglobulin with milk yield, fat yield, protein yield, fat percentage and protein percentage in both breeds during the three lactations. In the Brown Swiss, ${\kappa}$-casein phenotype was associated with 305-day fat yield and protein yield during the first lactation. ${\kappa}$-Casein AB was associated with higher milk, fat and protein yield during the second lactation. During the third lactation, ${\beta}$-lactoglobulin AA in Canadienne cows was associated with higher protein content in the milk (3.70%) when compared to phenotypes AB (3.54%) and BB (3.64%).

• Journal of Microbiology and Biotechnology
• /
• 제26권11호
• /
• pp.1993-2005
• /
• 2016

Bacillus pumilus is one of the most characterized microorganisms that are used for high-level production of select industrial enzymes. A novel B. pumilus SCU11 strain possessing high alkaline protease activity was obtained in our previous work. The culture supernatant of this strain showed efficient dehairing capability with minimal collagen damage, indicating promising potential applications in the leather industry. In this study, the strain's extracellular proteome was identified by LC-MS/MS-based shotgun proteomic analysis, and their related secretory pathways were characterized by BLAST searches. A total of 513 proteins, including 100 actual secreted and 413 intracellular proteins, were detected in the extracellular proteome. The functions of these secreted proteins were elucidated and four complete secretory systems (Sec, Tat, Com, and ABC transporter) were proposed for B. pumilus. These data provide B. pumilus a comprehensive extracellular proteome profile, which is a valuable theoretical and applicative basis for future genetic modifications and development of industrial enzymes.

• 대한수의학회지
• /
• 제38권2호
• /
• pp.328-335
• /
• 1998

Outer membrane proteins(OMPs) of Brucella abortus 1119-3 strain were extracted by Triton X-100 treatment, and fractionated by DEAE-cellulose column chromatography and Sephacryl S-300 column chromatography. The antigenic proteins in these fractions were identified by Western blot analysis. In Western blot analysis, a single band(38kDa) was observed in the DEAE fractions from 36th fraction to 38th fraction against sera of cattle infected with B abortus. And other fractions have several bands. However, the Sephacryl S-300 fractions exhibited a total of 3 peaks of proteins with a broad range from about 30 to 116kDa. In order to characterize further, the extracted OMPs and the DEAE fractions were analyzed by two dimensional polyacrylamide gel electrophoresis(2-DE) and Western blot using serum from naturally infected cattle with Brucella spp. The 2-DE immunoblots of DEAE fraction showed immunoreactive spots more than twenty two. The major protein spots have ranging from about 32 to 47kDa. The pI values of the spots were detected from pH 4.7 to 5.4. Among the major protein spots, the 38kDa protein which is a specific antigen, located at the point of approximately a pI 4.8.

• Journal of Microbiology and Biotechnology
• /
• 제16권2호
• /
• pp.286-290
• /
• 2006

A genomic library of Streptococcus vestibularis ATCC49124 was constructed in an E. coli plasmid vector, and the urease-positive transformants harboring the urease gene cluster were isolated on Christensen-urea agar plates. The minimal DNA region required for urease activity was located in a 5.6 kb DNA fragment, and a DNA sequence analysis revealed the presence of a partial ureI gene and seven complete open reading frames, corresponding to ureA, B, C, E, F, G, and D, respectively. The nucleotide sequence over the entire ure gene cluster and 3'-end flanking region of S. vestibularis was up to 95% identical to that of S. salivarius, another closely related oral bacterium, and S. thermophilus, isolated from dairy products. The predicted amino acid sequences for the structural peptides were 98-100% identical to the corresponding peptides in S. salivarius and S. thermophilus, respectively, whereas those for the accessory proteins were 96-100% identical. The recombinant E. coli strain containing the S. vestibularis ure gene cluster expressed a high level of the functional urease holoenzyme when grown in a medium supplemented with 1 mM nickel chloride. The enzyme was purified over 49-fold by using DEAE-Sepharose FF, Superdex HR 200, and Mono-Q HR 5/5 column chromatography. The specific activity of the purified enzyme was 2,019 U/mg, and the Michaelis constant ($K_{m}$) of the enzyme was estimated to be 1.4 mM urea. A Superose 6HR gel filtration chromatography study demonstrated that the native molecular weight was about 196 kDa.

• Asian-Australasian Journal of Animal Sciences
• /
• 제18권1호
• /
• pp.3-7
• /
• 2005

The insulin-like growth factors (IGFs), their receptors, and their binding proteins play key roles in regulating cell proliferation and apoptosis. Insulin-like growth factor binding protein-3 (IGFBP3, OMIM #146732) is one of the proteins that bind to the IGFs. IGFBP3 is a modulator of IGF bioactivity, and direct growth inhibitor in the extravascular tissue compartment. We identified twenty-two novel single nucleotide polymorphisms (SNPs) in IGFBP3 gene in Korean cattle (Hanwoo, Bos taurus coreanae) by direct sequencing of full gene including -1,500 bp promoter region. Among the identified SNPs, five common SNPs were screened in 650 Korean cattle; one SNP in promoter (IGFBP3 G-854C), one in 5'UTR region (IGFBP3 G-100A), two in intron 1 (IGFBP3 G+421T, IGFBP3 T+1636A), and one in intron 2 (IGFBP3 C+3863A). The frequencies of each SNP were 0.357 (IGFBP3 G-854C), 0.472 (IGFBP3 G-100A), 0.418 (IGFBP3 G+421T), 0.363 (IGFBP3 T+1636A) and 0.226 (IGFBP3 C+3863A), respectively. Haplotypes and their frequencies were estimated by EM algorithm. Six haplotypes were constructed with five SNPs and linkage disequilibrium coefficients (|D'|) between SNP pairs were also calculated. The information on SNPs and haplotypes in IGFBP3 gene could be useful for genetic studies of this gene.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제28권6호
• /
• pp.421-433
• /
• 2002

In order to elucidate the pathogenesis of cleft lip and palate, first of all, it is necessary to understand the developmental mechanisms of growth factors and extracellular matrix proteins in the tissues of cleft lip and palate. We have performed immunohistochemical studies on human cleft lip and palate tissues to elucidate the pathogenetic implications of cleft lip and palate. 16 specimens from postnatal human cleft lip and palate subjects and 17 specimens from autopsy of prenatal human cleft lip and palate were fixed in 10% buffered formalin, embedded in paraffin. The sections were routinely stained by hematoxylin and eosin, also stained by PAS, and followed by immunohistochemical stainings using the antiseras of growth factors and extracellular matrix proteins such as PCNA, S-100, c-erb-B2, MMP-3, MMP-10, HSP-70, transglutaninase-C, E-cadherin, VEGF, vWF. Both the prenatal and postnatal specimens of cleft lip and palate showed dysplastic proliferation of the basal cell layer, increased infiltration of melanocytes into mucosal epithelium, sebaceous gland hyperplasia ingrowing into the muscular tissue of lip and palate, and fatty infiltration into the submucosal deep connective tissue. The strong reactions of MMP-3 and HSP-70 were detected in the tissues of cleft lip and palate, especially increased in degenerating muscle bundles, while the immunostainings of PCNA and c-erb-B2 were weakly positive in the tissues of cleft lip and palate. These data suggest that the retrogressive tissue degeneration around the cleft areas persistently exist during the prenatal and postnatal period after cleft formation, and the sebaceous gland hyperplasia and fatty infiltration with the intense expression of MMP-3 and HSP-70 is closely related to the muscular degeneration around the cleft area.

• BMB Reports
• /
• 제30권1호
• /
• pp.60-65
• /
• 1997

Expression of human Cu.Zn-superoxide dismutase (SOD) with activity comparable to human erythrocyte enzyme was achieved in E. coli B21(DE3) by using the pET-17b expression vector containing a T7 promoter. Recombinant human SOD was found in the cytosol of disrupted bacterial cells and represented > 25% of the total bacterial proteins. The protein produced by the E. coli cells was purified using a combination of ammonium sulfate precipitation, Sephacryl S-100 gel filtration and DEAE-Sephacel ion exchange chromatography. The recombinant Cu,Zn-SOD and human erythrocyte enzyme were compared using dismutation activity, SDS-PAGE and immunoblotting analysis. The mass of the subunits was determined to be 15,809 by using a electrospray mass spectrometer. The copper specific chelator. diethyldithiocarbamate (DOC) reacted with the recombinant Cu,Zn-SOD. At $50{\mu}M$ and $100{\mu}M$ concentrations of DOC, the dismutation activity was not inhibited for one hour but gradually reduced after one hour. This result suggests that the reaction of DOC with the enzyme occurred in two distinct phases (phase I and phase II). During phase I of this reaction, one DOC reacted with the copper center, with retention of the dismutation activity while the second DOC displaced the copper, with a loss of activity in phase II.

• 운동영양학회지
• /
• 제25권4호
• /
• pp.45-53
• /
• 2021

[Purpose] In this study, we investigated whether a 70% ethanolic (EtOH) extract of Sargassum horneri had antioxidant and anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated macrophage-like RAW 264.7 cells. [Methods] The proximate composition, fatty acids, amino acids, and dietary fiber of S. horneri, various biologically active compounds, and antioxidant activity were analyzed. [Results] The DPPH and ABTS free radical scavenging activities, as well as the reduction power, of the S. horneri extract used here were significantly increased in a concentration-dependent manner. This indicates that S. horneri contains bioactive compounds, such as phenols and flavonoids, that have excellent antioxidant activity. The cellular viability and metabolic activity results confirmed that the extract had no discernible toxicity at concentrations up to 100 ㎍/mL. The levels of nitrites and cytokines (PGE₂, TNF-α and IL-6), which mediate pro-inflammatory effect, were significantly inhibited by treatment with either 50 or 100 ㎍/mL S. horneri extract, whereas that of IL-1β was significantly inhibited by treatment with 100 ㎍/mL of the extract. Similarly, the expression of iNOS and COX-2 proteins also decreased according to 50 or 100 ㎍/mL extract concentrations. NF-κB binding to DNA was also significantly inhibited by treatment with 100 ㎍/mL of extract. [Conclusion] These results suggest that 70% EtOH extracts of S. horneri can relieve inflammation caused by disease or high intensity exercise.

• Journal of Ginseng Research
• /
• 제39권2호
• /
• pp.125-134
• /
• 2015

Background: Black ginseng (Ginseng Radix nigra, BG) refers to the ginseng steamed for nine times and fine roots (hairy roots) of that is called fine black ginseng (FBG). It is known that the content of saponin of FBG is higher than that of BG. Therefore, in this study, we examined antitumor effects against MCF-7 breast cancer cells to target the FBG extract and its main component, ginsenoside Rg5 (Rg5). Methods: Action mechanism was determined by MTT assay, cell cycle assay and western blot analysis. Results: The results from MTT assay showed that MCF-7 cell proliferation was inhibited by Rg5 treatment for 24, 48 and 72 h in a dose-dependent manner. Rg5 at different concentrations (0, 25, 50 and $100{\mu}M$), induced cell cycle arrest in G0/G1 phase through regulation of cell cycle-related proteins in MCF-7 cells. As shown in the results from western blot analysis, Rg5 increased expression of p53, $p21^{WAF1/CIP1}$ and $p15^{INK4B}$ and decreased expression of Cyclin D1, Cyclin E2 and CDK4. Expression of apoptosiserelated proteins including Bax, PARP and Cytochrome c was also regulated by Rg5. These results indicate that Rg5 stimulated cell apoptosis and cell cycle arrest at G0/G1 phase via regulation of cell cycle-associated proteins in MCF-7 cells. Conclusion: Rg5 promotes breast cancer cell apoptosis in a multi-path manner with higher potency compared to 20(S)-ginsenoside Rg3 (Rg3) in MCF-7 (HER2/ER+) and MDA-MB-453 (HER2+/ER) human breast cancer cell lines, and this suggests that Rg5 might be an effective natural new material in improving breast cancer.