• Journal of Microbiology and Biotechnology
• /
• v.26 no.1
• /
• pp.160-170
• /
• 2016

The increasing spread of antibiotic-resistant pathogens has raised the interest in alternative antimicrobial treatments. In our study, the functionally active gram-negative bacterium bacteriophage CP933 endolysin was produced in Nicotiana benthamiana plants by a combination of transient expression and vacuole targeting strategies, and its antimicrobial activity was investigated. Expression of the cp933 gene in E. coli led to growth inhibition and lysis of the host cells or production of trace amounts of CP933. Cytoplasmic expression of the cp933 gene in plants using Potato virus X-based transient expression vectors (pP2C2S and pGR107) resulted in death of the apical portion of experimental plants. To protect plants against the toxic effects of the CP933 protein, the cp933 coding region was fused at its Nterminus to an N-terminal signal peptide from the potato proteinase inhibitor I to direct CP933 to the delta-type vacuoles. Plants producing the CP933 fusion protein did not exhibit the severe toxic effects seen with the unfused protein and the level of expression was 0.16 mg/g of plant tissue. Antimicrobial assays revealed that, in contrast to gram-negative bacterium E. coli (BL21(DE3)), the gram-positive plant pathogenic bacterium Clavibacter michiganensis was more susceptible to the plant-produced CP933, showing 18% growth inhibition. The results of our experiments demonstrate that the combination of transient expression and protein targeting to the delta vacuoles is a promising approach to produce functionally active proteins that exhibit toxicity when expressed in plant cells.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.39 no.11
• /
• pp.1654-1659
• /
• 2010

In order to utilize squid liver by-products, which is normally discarded as industrial waste in the process of squid manufacturing, salt-fermented squid liver sauce was prepared experimentally and also tested for inhibitory activity against angiotensin converting enzyme (ACE). ACE inhibitory activity of squid liver sauce was increased with the elapse of fermentation days until 12 months, followed by a constant level of inhibitory activity thereafter. 15-month-old sauce ($IC_{50}=29.66\;{\mu}g$) was filtered through PM-10 membrane (M.W. cut-off 10,000 Da) to obtain the peptides fractions with ACE inhibition activity. Filtered fractions were applied to a Bio-gel P-2 column and three active fractions (A, B and C) were collected. Among them, fraction B applied to a SuperQ-Toyopearl 650S column chromatography lead to the isolation of active B-1 fraction. It has the ACE inhibitory activity ($IC_{50}=5.46\;{\mu}g$). The main composition of its amino acids is lysine, glycine and proline, which cover about 85% of the total amino acids.

• Korean Journal of Weed Science
• /
• v.17 no.1
• /
• pp.44-51
• /
• 1997

Glyphosate had no effect on 5-enolpyruvylshikimate-3-phosphate synthase(EPSP-synthase) biosynthesis per se. But it inhibited clealy the activity of EPSP-synthase. EPSP-synthase seemed to be synthesized as a higher molecular weight(54 kDa) presusor protein and to be transported into plastid. The apparent molecular weight of mature EPSP-synthase in plastid is 45 kDa. Thus, the molecular size of transit peptide appeared to be about 9 kDa. The etiolation for 48 h after glyphosate application did not exhibit the inhibition of translocating level of EPSP-synthase across chloroplast envelope in actively growing meristematic leaves. But even when the plants were etiolated 2 hr after glyphosate treatment, a complete inhibition did not occur at least within 12 hr, i.e. 2 hr after beginning light period, suggesting that EPSP-synthase biosynthesis appeared to be not completely light dependent and the level of EPSP-synthase translocation to chloroplast could be controlled by an unknown regulatory mechanism of light dependent herbicidal effect of glyphosate.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.26 no.1
• /
• pp.42-46
• /
• 2022

Purpose In the meantime, there have been not many samples that require dilution, and it has been difficult for the examiner to set an appropriate dilution multiple for RIA test item and report the results. Accordingly, it was judged that it was necessary to set the maximum dilution multiple for each test and to verify the upper limit of the clinical reportable range. Therefore, in this study, the maximum dilution multiple for each RIA test was set and the upper limit of the clinical reportable range was verified accordingly Materials and Methods Among all RIA tests conducted at Asan Medical Center, the study treated on 30 types of tests which also conduct the dilution test. Data from March to July 2021 were collected and analyzed. The study was conducted on samples subjected to serial dilutions such as X2, X4 or X10, X10², X10³, X10⁴, X10⁵. Results Among a total of 30 test types, 18 test types have more than 5 N values in the tolerance range of 80~120%. As a result of the verification of maximum dilution multiples, the test set to 10⁴ is 𝛼-fetoprotein and thyroglobulin, and the test set to 10³ is CA-125, CEA, and 𝛽-hCG, and the test set to 10² is Free PSA, PSA, CA15-3, SCC, Ferritin, PTH, Cortisol, and Calcitonin. Tests set to 10 include three categories: 𝛽2-Microglobulin, C-peptide, and Testosterone. Conclusion It is expected that it will contribute to improving the quality of nuclear medicine blood tests as the results of dilution experiments can be reported quickly and accurately through the verification of the clinical reportable range.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.42 no.11
• /
• pp.1759-1766
• /
• 2013

In this study, the optimal conditions for salmon hydrolysate using squid liver and compositional properties of hydrolysate were investigated. The optimal conditions were $55^{\circ}C$, pH 5.5 and 0.66~0.67% (w/w) in the ratio of squid liver to acidic and thermal treated salmon muscle. The free amino acid of hydrolysate from the acidic treated salmon muscle was higher than that of hydrolysate from the thermal treated salmon muscle, while the total amino acid and mineral were high in the acidic treated salmon muscle. Furthermore, cadmium of hydrolysate from the thermal denatured salmon muscle was below 2 ppm, and has an acceptable level as potential ingredient. The distribution of peptide molecular weight was 40.0% for 1.0~9.5 kDa, 6.7% for 0.5 kDa, and 47.4% of others in hydrolysate from the thermal treated salmon muscle. Both hydrolysates did not show any toxicity against the HepG2 cell line for up to $200{\mu}g/mL$.

• The Korean Journal of Physiology
• /
• v.23 no.1
• /
• pp.89-98
• /
• 1989

In order to produce antibody for use in radioimmunoassay of gastrin in physiological concentration, four rabbits of New Zealand white were immunized with synthetic human gastrin-17-I conjugated to hemocyanin with EDC. Among them, only one rabbit produced antibody that could bind 50% of $^{125}I-gastrin$ at a final dilution of 1:25,000. $^{125}I-gastrin$ was prepared with synthetic human gastrin-17-I and $NaI^{125}$ by lactoperoxidase technique. The product was then purified on a column of Sephadex Gl5/G5O (7:3, w/w) followed by a column of DEAE sephadex A-25. The specific radioactivity of the purified $^{125}I-gastrin$ was in the range of 347-1429 ${\mu}Ci/nmole$ when determined by the self-displacement method. The effective affinity constant $(K_{eff})$, total binding sites (N), heterogeneity index $({\alpha})$ and average affinity constant $(K_{0})$ of the anti-gastrin serum calculated from Scatchard plot as well as Sips plot were $1.77{\times}10^{11}/M$, 255 nM, 0.84 and $0.79{\times}10^{11}/M$, respectively. When radioimmunoassay was performed with the anti-gastrin serum, it was confirmed that the mean concentration of gastrin immunoreactivity in plasma was increased by feeding in humans and rats, and also increased by bombesin administration in rats. The results indicate that the anti-gastrin serum produced in the present investigation is suitable for radioimmunological determination of gastrin in physiological concentration.

• Korean Journal of Weed Science
• /
• v.12 no.4
• /
• pp.368-373
• /
• 1992

The effect of alachlor treatment on protein synthesis was studied. Protein synthesis was inhibited by $1{\times}10^{-4}$ M and $1{\times}10^{-3}$M of alachlor 5.8% and 86.5%, respectively, while did not occur blow $1{\times}10^{-5}$M alachlor. Soluble protein of alachlor treated oat root tips was examined by polyacrylamide gel electrophoresis. The proteins extracted from oat root tips showed that they were made up of subunits blow 100 kd polypeptides by SDS-PAGE. As compared to control, high molecular proteins(above 47 kd) were inhibited of oat root treated with alachlor, while low molecular proteins(below 23 kd) were increased. Two-D gels showed that alachlor caused decrease(1-6 spots) or increase(7-10 spots) in number of polypeptides on silver staining. The intensity of some polypeptides of soluble proteins (molecular mass of 83 kd : 1, 2 spots, 70 kd : 3, 4 spots, and 47.5 kd : 5, 6 spots) decreased in alachlor treatment, whereas the intensity of other peptide bands (20 kd : 7 spot and 16 kd : 8, 9, 10 spots) increased. Oat root tip proteins present in the neutral zone are masked by diffusing of major proteins, but proteins in acid zone are resolved minor proteins.

• Radiation Oncology Journal
• /
• v.21 no.1
• /
• pp.54-65
• /
• 2003

Purpose : To analyze the gene expression Profiles of uterine ceulcal cancer, and its variation after radiation therapy, with or without concurrent chemotherapy, using a CDNA microarray. Materials and Methods :Sixteen patients, 8 with squamous ceil carcinomas of the uterine cervix, who were treated with radiation alone, and the other 8 treated w14h concurrent chemo-radiation, were Included in the study. Before the starling of the treatment, tumor biopsies were carried out, and the second time biopsies were peformed after a radiation dose of 16.2$\~$27 Gy. Three normal cervix tissues were used as a control group. The microarray experiments were peformed with 5 groups of the total RNAs extracted individually and then admixed as control, pre-radiation therapy alone, during-radiation therapy alone, pre-chemoradiation therapy, and during-chemoradlation therapy. The 33P-iabeled CDNAS were synthesized from the total RNAs of each group, by reverse transcription, and then they were hybridized to the CDNA microarray membrane. The gene expression of each microarrays was captured by the intensity of each spot produced by the radioactive isotopes. The pixels per spot were counted with an Arrayguage, and were exported to Microsoft Excel The data were normalized by the Z transformation, and the comparisons were peformed on the Z-ratio values calculated. Results : The expressions of 15 genes, including integrin linked kinase (ILK), CDC28 protein kinase 2, Spry 2, and ERK 3, were increased with the Z-ratio values of over 2.0 for the cervix cancer tissues compared to those for the normal controls. Those genes were involved In cell growth and proliferation, cell cycle control, or signal transduction. The expressions of the other 6 genes, Including G protein coupled receptor kinase 5, were decreased with the Z-ratio values of below -2.0. After the radiation thorapy, most of the genes, with a previously Increase expressions, represented the decreased expression profiles, and the genes, with the Z-ratio values of over 2.0, were cyclic nucleotlde gated channel and 3 Expressed sequence tags (EST). In the concurrent chemo-radiation group, the genes involved in cell growth and proliferation, cell cycle control, and signal transduction were shown to have increased expressions compared to the radiation therapy alone group. The expressions of genes involved in anglogenesis (angiopoietln-2), immune reactions (formyl peptide receptor-iike 1), and DNA repair (CAMP phosphodiesterase) were increased, however, the expression of gene involved In apoptosls (death associated protein kinase) was decreased. Conclusion : The different kinds of genes involved in the development and progression of cervical cancer were identified with the CDNA microarray, and the proposed theory is that the proliferation signal stalls with ILK, and is amplified with Spry 2 and MAPK signaling, and the cellular mitoses are Increased with the increased expression oi Cdc 2 and cell division kinases. After the radiation therapy, the expression profiles demonstrated 4he evidence of the decreased cancer cell proliferation. There was no sigificant difference in the morphological findings of cell death between the radiation therapy aione and the chemo-radiation groups In the second time biopsy specimen, however, the gene expression profiles were markedly different, and the mechanism at the molecular level needs further study.

• The Korean Journal of Pharmacology
• /
• v.28 no.2
• /
• pp.147-162
• /
• 1992

The objectives of the present experiments were to characterize the effects of the peptides belonging to the pancreatic polypeptide family on the contractility of cerebral arteries and to observe the interactions of these peptides with the cyclic nucleotide activators and the potassium channel openers. Dogs of either sex, $20{\sim}30\;Kg$ in weight, were sacrificed. Basilar and middle cerebral arteries from brain were isolated and prepared for myography in the PSS equilibrated with 95% $O_2$ and 5% $CO_2$ at $37^{\circ}C$. The endothelial cells of the spiral strips were removed by CHAPS solution (0.3% w/v, 15 seconds). 1. PP, PYY and NPY contracted the arterial strips concentration-dependently with a rank order of potency of PYY>NPY>PP. These peptides were 20 to 200 times more potent than norepinephrine, and only PYY showed a greater potency than 5-HT. 2. Cyclic nucleotide activators, forskolin (for cAMP) and sodium nitroprusside (for cGMP) reduced the basal tone and inhibited the PP-, PYY- and NPY- induced contractions by concentration-dependent manners. Forskolin was more potent in reducing basal tone than sodium nitroprusside. 3. Potassium channel openers, RP 49356, P 1060 and BRL 38227 reduced the basal tone concentration-dependently and tended to inhibit the PP-, PYY- and NPY- induced contractions. Notably, BRL 38227 with low concentration $(0.1\;{\mu}M)$ enhanced the contractions induced by those peptides while P 1060 inhibited the contractions concentration-dependently. 4. The combinations of the cyclic nucleotide activators and the potassium channel openers were slightly additive in reducing the basal tone. P 1060 and BRL 38227 enhanced the relaxant effect of sodium nitroprusside significantly. On the PYY-induced contration $(0.1\;{\mu}M)$, $K^+$ channel openers tended to inhibit the inhibitory actions of forskolin and sodium nitroprusside. P 1060 and BRL 38227 antagonized the inhibitory action of sodium nitroprusside significantly. The results of the present study may be summarized that in canine cerebral arteries, not only NPY but also PYY may play a role in a cerebrovascular spasm, and intracellular concentration of either cAMP or cGMP may be involved in the mechanism of vasoconstrictive actions of these peptides, which may be affected either positively or negatively by a $K^+$ channel opener.