• Journal of Microbiology and Biotechnology
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• v.34 no.7
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• pp.1385-1394
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• 2024

Collagenolytic proteases are widely used in the food, medical, pharmaceutical, cosmetic, and textile industries. Mesophilic collagenases exhibit collagenolytic activity under physiological conditions, but have limitations in efficiently degrading collagen-rich wastes, such as collagen from fish scales, at high temperatures due to their poor thermostability. Bacterial collagenolytic proteases are members of various proteinase families, including the bacterial collagenolytic metalloproteinase M9 and the bacterial collagenolytic serine proteinase families S1, S8, and S53. Notably, the C-terminal domains of collagenolytic proteases, such as the pre-peptidase C-terminal domain, the polycystic kidney disease-like domain, the collagen-binding domain, the proprotein convertase domain, and the β-jelly roll domain, exhibit collagen-binding or -swelling activity. These activities can induce conformational changes in collagen or the enzyme active sites, thereby enhancing the collagen-degrading efficiency. In addition, thermostable bacterial collagenolytic proteases can function at high temperatures, which increases their degradation efficiency since heat-denatured collagen is more susceptible to proteolysis and minimizes the risk of microbial contamination. To date, only a few thermophile-derived collagenolytic proteases have been characterized. TSS, a thermostable and halotolerant subtilisin-like serine collagenolytic protease, exhibits high collagenolytic activity at 60℃. In this review, we present and summarize the current research on A) the classification and nomenclature of thermostable and mesophilic collagenolytic proteases derived from diverse microorganisms, and B) the functional roles of their C-terminal domains. Furthermore, we analyze the cleavage specificity of the thermostable collagenolytic proteases within each family and comprehensively discuss the thermostable collagenolytic protease TSS.

• Bulletin of the Korean Chemical Society
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• v.25 no.6
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• pp.838-842
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• 2004

Amyloid peptide (A${\beta}$) is the major component of senile plaques found in the brain of patient of Alzheimer's disease. ${\beta}$-amyloid peptide (25-35) (A${\beta}$25-35) is biologically active fragment of A${\beta}$. The three-dimensional structure of A${\beta}$25-35 in aqueous solution with 50% (vol/vol) TFE determined by NMR spectroscopy previously adopts an ${\alpha}$-helical conformation from $Ala^{30}$ to $Met^{35}$. It has been proposed that A${\beta}$(25-35) exhibits pH- and concentration-dependent ${\alpha}-helix{\leftrightarrow}{\beta}$sheet transition. This conformational transition with concomitant peptide aggregation is a possible mechanism of plaque formation. Here, in order to gain more insight into the mechanism of ${\alpha}$-helix formation of A${\beta}$25-35 peptide by TFE, which particularly stabilizes ${\alpha}$-helical conformation, we studied the secondary-structural elements of A${\beta}$25-35 peptide by molecular dynamics simulations. Secondary structural elements determined from NMR spectroscopy in aqueous TFE solution are preserved during the MD simulation. TFE/water mixed solvent has reduced capacity for forming hydrogen bond to the peptide compared to pure water solvent. TFE allows A${\beta}$25-35 to form bifurcated hydrogen bonds to TFE as well as to residues in peptide itself. MD simulation in this study supports the notion that TFE can act as an ${\alpha}$-helical structure forming solvent.

• Journal of Pharmacopuncture
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• v.22 no.1
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• pp.28-34
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• 2019

Background: Breast cancer is a complex, heterogeneous disease and one of the most common malignancies in women worldwide. The efficacy of chemotherapy as an important breast cancer treatment option has been severely limited because of the inherent or acquired resistance of cancer cells. The molecular chaperone heat shock protein 90 (HSP90) upregulated in response to cellular stress is required for functions such as conformational maturation, activation and stability in more than 200 client proteins, mostly of the signaling type. In this study, the expression of HSP90 isoforms including $HSP90{\alpha}$ and $HSP90{\beta}$ in breast cancer cell lines before and after treatment with doxorubicin (DOX) was assessed. Material and Methods: The cell cytotoxicity of DOX in MDA-MB-231 and MCF-7 cell lines was determined using the MTT assay. immunofluorescence and western blotting techniques were used to determine the expression of $HSP90{\beta}$ in the cell lines before and after DOX treatment. Immunofluorescence was also conducted to ascertain the expression of $HSP90{\alpha}$. Results: The MTT assay results showed that the MDA-MB-231 cells ($IC_{50}=14.521{\mu}M$) were more sensitive than the MCF-7 cells ($IC_{50}=16.3315{\mu}M$) to DOX. The immunofluorescence results indicated that the expression of $HSP90{\alpha}$ in both cell lines decreased after exposure to DOX. The western blot and immunofluorescence analyses showed that $HSP90{\beta}$ expression decreased in the MCF-7 cells but increased in the MDA-MB-231 cells after DOX treatment. Conclusion: The obtained results suggested that $HSP90{\alpha}$ and $HSP90{\beta}$ expression levels were reduced in the MCF-7 cells after exposure to DOX. In the MDA-MB-231 cells, $HSP90{\alpha}$ expression was reduced while $HSP90{\beta}$ was found to be overexpressed following DOX treatment.

• Journal of Chest Surgery
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• v.38 no.12 s.257
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• pp.835-843
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• 2005

Background: Cancer of the esophagus is one of the most malignant tumors with poor prognosis. The p53 gene alteration, over expression of Cyclin D1, and Ki67 index were thought to be the prognostic factors. However, their clinical significances in esophageal squamous cell carcinoma are controversial and p53 accumulation may not correlate with genetic mutation. The current study investigates their prognostic significance in squamous cell carcinoma of the esophagus. Material and Method: The Subjects studied were 124 esophageal squamous cell carcinoma patients who underwent esophagectomy. The mutation of p53, over expression of Cyclin D1, Ki67 labelling index, mitotic index were examined by using an immunohistochemical staining. We compared the results and investigated the correlation with the mutation of p53, overexpression of Cyclin D1, Ki67 labelling index, mitotic index and tumor size, and duration of survival. Result: There was no correlation between the results in immunohistochemical staining according to age, sex, tumor size, Iymph node status, and clinical stage of the disease. Mutant p53 protein was found in 69 cases (55.6$\%$). Median survival time was 21 months in cases with negative for mutant p53 protein and 22 months in positive cases. There was no significant difference in survival (p=0.46). Median survival time was 22 months in cases with negative for Cyclin D1 and 16 months in positive cases (p=0.18). Median and mean survival time was 22 months and 36 months when Ki67 labeling index was 40 or less (102 cases). Median and mean survival was 16 months and 23 months, when Ki67 labeling index was more than 40 (22 cases). There was significant difference in survival rate (p=0.011). Conciusion: Positivity of p53 and cyclin D1 was not useful in predicting the prognosis in our study. There was no significant correlation among mutant p53 protein accumulation, Cyclin D1 over expression, and Ki67 labeling index. However, in several studies, PCR single strand conformational polymorphism analysis of p53 showed a correlation to the prognosis. We thought that there was a significant discordance between p53 gene mutation and mutant p53 protein accumulation. When Ki67 labeling index was more than 40, prognosis was poorer, Ki67 seems to be a prognostic factor in our study. Therefore, we confirmed the possibility of using molecular markers as prognostic factors.