• KSBB Journal
• /
• v.24 no.5
• /
• pp.458-462
• /
• 2009

Silk fibroin is a structural protein from Bombyx mori and can be sulfated to provide biofunctional polypeptides showing antiviral and anticoagulating activities. However, the sulfated fibroins have not been characterized enough to present their compositions and structures. In this report, sulfation reaction was investigated by varying the reaction temperature and sulfuric acid concentration and analysis of the resulting peptides were carried out. The degree of sulfation was proportion to sulfuric acid concentration but the maximum product yield was obtained at $60^{\circ}C$ and 5% of sulfuric acid concentration. FT-IR spectrum, UV absorption and NMR spectrum support that o-sulfate ester was formed at the hydroxyl group of serine and tyrosine residues. Size exclusion chromatography identified that sulfated fibroin was composed of a highly hydrolyzed polypeptide mixtures and peptides of relatively higher molecular weight.

• Proceedings of the Korean Society for Applied Microbiology Conference
• /
• 2001.06a
• /
• pp.155-157
• /
• 2001

Bifidobacterium spp. is nonpathogenic, gram-positive and anaerobic bacteria, which inhabit the intestinal tract of humans and animals. In breast-fed infants, bifidobacteria comprise morethan 90％ of the gut bacterial population. Bifidobacteria spp. are used in commericial fermented dairy products and have been suggested to exert health promoting effects on the host by maintaining intestinal microflora balances, improving lactose tolerance, reducing serum cholesterol levels, increasing synthesis of vitamins, and aiding the immune enchancement and anticarcinogenic activity for the host. These beneficial effects of Bifidobacterium are strain-related. Therefore continued efforts to improve strain characteristics are warranted. in these respect, development of vector system for Bifidobacterium is very important not only for the strain improvement but also because Bifidobacterium is most promising in serving as a delivery system for the useful gene products, such as vaccine or anticarcinogenic polypeptides, into human intestinal tract. For developing vector system, we have characterized several bifidobacterial plasmids at genetic level and developed several shuttle vectors between E. coli and Bifidobacterium using them. Also, we have cloned and sequenced several metabolic genes and food grade selection marker. Also we have obtained bifidobacterial surface protein, which will be used as the mediator for surface display of foreign genes. Recently we have succeeded in expressing amylase and GFP in Bifidobacterium using our own expression vector system. Now we are in a very exciting stage for the molecular breeding and safe delivery system using probiotic Bifidobacterium strains.

• Journal of Oriental Neuropsychiatry
• /
• v.12 no.1
• /
• pp.137-149
• /
• 2001

Cytokines are polypeptides which possess various biological properties affecting. host defense function and response to disease. Inflammatory cytokines, tumor necrosis $factor-{\alpha}$(TNF-${\alpha}$), interleukin(IL)-1 and IL-6 induce inflammation, fever, hypotension and pain when injected into animals or human subject. When glial cell cultures were prepared from neonatal mice or rats, astrocytes were reported to produce these inflammatory cytokines to viral infection, lipopolysaccharide(LPS), or cytokines. The purpose of this study was to investigate the regulatory effect of these cytokines secretion from primary cultures of rat astrocytes. Substance P(SP) can stimulate secretion of TNF-${\alpha}$ from astrocytes stimulated with LPS. Sesim-Tang significantly inhibited the TNF-${\alpha}$ secretion by astrocytes stimulated with SP and LPS. IL-1 has been shown to elevate TNF-${\alpha}$ secretion from LPS-stimulated astrocytes while having no effect on astrocytes in the absence of LPS. We therefore also investigated whether IL-1 mediated inhibition of TNF-${\alpha}$ secretion from primary astrocytes by Sesim-Tang. Treatment of Sesim-Tang to astrocytes stimulated with both LPS and SP decreased IL-1 secretion significantly. The secretion of TNF-${\alpha}$ by LPS and SP in astrocytes was progressively inhibited with increasing amount of IL-1 neutralizing antibody. Furthermore Sesim-Tang inhibited the IL-6 secretion by astrocytes stimulated with SP and LPS. The inhibitory effect of inflammatory cytokines by Sesim-Tang, observed in this study, might reflect an antiinflammatory activity and a reduction of various-type pains, fever etc. in the central nervous system.

• Parasites, Hosts and Diseases
• /
• v.53 no.4
• /
• pp.483-488
• /
• 2015

This report describes the molecular characterization of the Tc8.2 gene of Trypanosoma cruzi. Both the Tc8.2 gene and its encoded protein were analyzed by bioinformatics, while Northern blot and RT-PCR were used for the transcripts. Besides, immunolocalization of recombinant protein was done by immunofluorescence and electron microscopy. Analysis indicated the presence of a single copy of Tc8.2 in the T. cruzi genome and 2-different sized transcripts in epimastigotes/amastigotes and trypomastigotes. Immunoblotting showed 70 and 80 kDa polypeptides in epimastigotes and trypomastigotes, respectively, and a differential pattern of immunolocalization. Overall, the results suggest that Tc8.2 is differentially expressed during the T. cruzi life cycle.

• Korean Journal of Veterinary Research
• /
• v.29 no.1
• /
• pp.27-35
• /
• 1989

To develop more specific and sensitive diagnostic methods for infectious bovine rhinotracheitis, 7-C-2 monoclonal antibody specific to polypeptides of infectious bovine rhinotracheitis virus (IBRV) was applied in indirect immunofluorescence antibody assay (IFA), indirect immunoperoxidase assay(IPA) and radial immunodiffusion enzyme assay (RIDEA). It was found that IBRV infected in MDBK cells could be detected as early as 8 hours post infection by IFA, and that IFA was more rapid and specific to identify IBRV antigen than IPA. The diagnostic efficacy of RIDEA and SN test was studied with 88 bovine sera. It was evident that RIDEA could eliminate the false positive reaction encountered in serum neutralization(SN) test, being more rapid and sensitive than the latter. Highly significant correlation coefficiency (r=0.76, p<0.01) was evaluated between the titers of sera and the diameters of RIDEA. Tracheal membranes and sera collected from 96 slaughtered cattle with lesions in respiratory organs were examined to detect IBRV antigen and antibody by IFA, RIDEA and SN test. It was presented that positive rates were 32.3% in IFA, 20.8% in RIDEA and 21.9% in SN test, and that coincidence rate between RIDEA and SN test were 100% in positive sera and 98.7% in negative sera. In conclusion, it was assumed that application of monoclonal antibody could improve the diagnostic efficacy of IBR by enhancing sensitivity and specificity of IPA, IFA and RIDEA.

• Korean Journal of Veterinary Research
• /
• v.39 no.4
• /
• pp.751-759
• /
• 1999

Plaque characteristics of porcine reproductive and respiratory syndrome (PRRS) virus isolates were examined using MARC-145 line cells. The plaque morphology of PRRS virus isolates was variable in size and heterogenic in population. Upon serial passages of the PRRS virus isolates on MARC-145 tells, heterogeneity was maintained but numbers of the large plaque size virus were increased with certain isolates. A PRRS virus isolate with variable plaque sizes was subcloned into 2 populations : small plaque ($H_S$) and large plaque ($H_L$) viruses. Growth kinetics of the subclones were then determined in MARC-145 cells, and production of the structural polypeptides was analyzed by SDS-PAGE. In a comparison of the growth kinetics, the $H_S$ virus showed higher infectivity titers during the first 48 hours but slower to reach the peak titier than $H_L$ virus did. In a nucleotide sequence comparison, differences of 4 nucleotides in open reading frames 5-6 gene were found between $H_S$ and $H_L$ viruses. Both the $H_S$ and $H_L$ clones produced 5 polypeptide bands with molecular weights of 15, 19, 26, 36 and 42 kD. The 5 bands were detected at 48 hours postinoculation (PI) with antisera to $H_L$ and another large plaque virus ($W_L$) and at 72 hours PI with $H_S$ virus antiserum. The present results demonstrate differences of biologic and molecular characteristics between the two PRRS virus plaque clones.

• Journal of Life Science
• /
• v.9 no.1
• /
• pp.29-34
• /
• 1999

Cotyledon and hypocotyl explants of perilla were cultured on MS medium containing a combined concentration of BA(0.5, 1.0 and 1.5mg/$\ell$) and NAA(0.1, 0.5 and 2.0mg/$\ell$) in order to regenerate the explant and induce the callus. The best regeneration of the explant and induction of the callus were observed in a combined concenteration of 0.5mg/$\ell$ of BA and 0.5mg/$\ell$ NAA both in cotyledon and hypocotyl explants. In cotyledon explants, rooting was achieved upon transferring shoots to MS medium containing 0.5mg/$\ell$ of BA and 0.1mg/$\ell$ of NAA. We also investigated the change of protein and RNA content on developmental stage of callus and plant regeneration of perilla. Protein content was increased but RNA content was decreased as the culture period increases. The banding pattern of polypeptide revealed that both 30KD and 45KD polypeptides were obvious in cotyledon obtained from pre-culture explants, but only 30KD polypeptide was further getting obvious as the culture period increases.

• Pediatric Infection and Vaccine
• /
• v.3 no.2
• /
• pp.133-138
• /
• 1996

Purpose : In the treatment of MRSA infection, rapid detection of MRSA is extremely important. The mecA gene codes the new drug resistant polypeptides called PBP2' which mediates the clinically relevant resistance to all beta-lactam antibiotics. The identical mecA gene has been found in coagulase-negative staphylococcus with the methicillin-resistant phenotype. On the other hand, the femA gene was absent from coagulase negative staphylococcus strains with the methicillin resistant phenotype. This study is aimed at early detection and definite diagnosis of MRSA. Methods : A total of 24 MRSA strains were studied. All strains were tested for antimicrobial susceptibility and purified DNA. We amplified both mecA and femA genes by PCR in 24 strains. Results : In MRSA all the 16 strains (100%) carried femA gene and 11 strains (68.7%) carried mecA gene. In contrast, in methicillin sensitive staphylococcus all the 8 strains (100%) carried femA and only 3 strains (37.5%) were detected mecA. Conclusions : As results, there are difference in the phenotype and genotype of methicillin resistance by PCR of mecA and femA. Such disparities between methicillin resistance and the presence of mecA gene suggest the presence of control gene of the mecA.

• Journal of Pharmaceutical Investigation
• /
• v.25 no.3
• /
• pp.177-184
• /
• 1995

In order to formulate an aqueous topical preparation of epidermal growth factor(EGF) for the treatment of open wound and bum, the stability of EGF in aqueous vehicles containing various stabilizers was evaluated and the pharmacological activity of gel preparations formulated with poloxamer 407 was determined with wound model. Various additives, which are known as potent stabilizers for proteins and polypeptides so far, were used to increase the stability of EGF in aqueous vehicles. The contents of EGF in the vehicles containing stabilizers were determined with an HPLC method after the storage at $37^{\circ}C$. EGF was more stable in ultrapure water than RO water or saline. All the additives studied resulted in deleterious effects on EGF stability. Therefore, it was speculated that any additives or impurities in the vehicle made EGF unstable. However, nitrogen purge of solution increased the stability of EGF in aqueous vehicles. The aqueous topical preparations of EGF were formulated with poloxamer 407 as a gel base in saline. Gelatin or amastatin was employed as a protease inhibitor. The pharmacological effect of EGF gel was studied with open wound model in mice. EGF preparations, made of oleaginous base or poloxamer gel base, showed significant healing effect compared to the control group(p<0.05). The addition of protease inhibitor in poloxamer 407 gel resulted in significant healing effect compared to the gel without it(p<0.05). Body weights of mice treated with EGF preparation were increased at the first day after the formation of open wound, while those of the control group were decreased. The EGF gel made of poloxamer 407 containing a pretense inhibitor would be a promising aqueous topical preparation for EGF.

• Journal of Life Science
• /
• v.21 no.3
• /
• pp.473-479
• /
• 2011

Adenylyl cyclase (AC) catalyzes the formation of cyclic AMP (cAMP) from ATP. The cAMP produced by AC serves as a secondary messenger in a variety of signal transduction pathways, and controls various cellular functions in many organisms. ACs can be grouped into six classes based on their primary amino acid sequences. Eukaryotes and mycobacteria contain only members of class III AC. The catalytic cyclase domains of class III AC are active as dimers: mammalian ACs, which are composed of a single polypeptide with two catalytic cyclase domains, form the active site as a result of intramolecular dimerization of the catalytic cyclase domains. In contrast, mycobacterial ACs function as homodimers, since their polypeptides contain a single catalytic cyclase domain. Six amino acids are required for the catalytic activity of class III AC - two aspartate residues, a lysine-aspartate pair and an arginine-asparagine pair. 16 ACs belonging to the class III were identified in Mycobacterium tuberculosis H37Rv, and their characteristics are reviewed.