• Korean Journal of Pharmacognosy
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• v.25 no.2
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• pp.121-131
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• 1994

Two kinds of new lectins, CATL-I and CATL-II, were partially purified from the intestine of Chlorostoma argyrostoma turbunatum by physical saline extraction, salt fractionation, ion exchange chromatography and gel filtration. CATL-I and CATL-II were purified 39.4 and 15.8 fold with a yield of 8.8 and 7.4%, respectively. On polyacrylamide gel electrophoresis, CATL-I demonstrated one major and one minor bands. This lectin agglutinated human and other animal erythrocytes nonspecifically and also agglutinated murine splenic lymphocytes. Carbohydrate specificity of the lectins was determined by inhibition of the agglutinability by methyl-${\alpha}-_D$-galactopyranoside and $_L-rhamnose$ at a final concentration of 6 mM. The lectins contained relatively high amounts of acidic amino acids, but the contents of sulfur containing amino acids were very low or was not estimated. Immunochemical studies were carried out to identify some properties of marine animal lectins.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.317.1-317.1
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• 2003

Carbohydrate-binding proteins have been isolated from various sources, including plants, animals, fungi, and bacteria, and they have been used extensively in the detection, localization, and isolation of glycoconjugates. Many carbohydrate-binding proteins are purified from mushrooms, however, only a few proteins with sialic acid-binding specificity have been reported. In the present study, a novel sialic acid-binding protein, designated PJA, has been purified from the mushroom Paecilomyces japonica. followed by extraction and affinity chromatography. (omitted)

• YAKHAK HOEJI
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• v.47 no.3
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• pp.176-179
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• 2003

A library of unlimited number of novel lectins with diverse specificities has been previously generated by randomly mutating the carbohydrate-recognition domain of Maackia amurensis hemagglutinin (MAH). To establish the experimental environment capable of selecting high affinity mutant lectins in E. coli, phage display system was adapted. Carbohydrate binding capacity of two phagemid vectors, pComb3 and pComb8 displaying wild-type MAH lectin was assessed. Specific bindings of pComb3 and pComb8 phages expressing w.t. MAH to affinity-purified polyclonal anti-MAH antibody and to glycophorin was demonstrated. Both phages also showed strong hemagglutinating activity to intact but not sialidase-treated human erythrocytes, which is consistent to the specificity of native MAH. Taken together, two different phage display vectors successfully allowed the expression of active MAH as a fusion protein on the surface of bacteriophage, which will lead to preparation of unique plant lectins with high affinity toward a variety of carbohydrate chains.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2004.06a
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• pp.215-218
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• 2004

Dextrans make up a class of polysaccharides that are D-glucans of various structures with contiguous $\alpha$-1longrightarrow6 ~6 glycosidic linkages in the main chains and $\alpha$-1longrightarrow2, $\alpha$-1longrightarrow3, or $\alpha$-1longrightarrow4 branch glycosidic linkages, depending on the specificity of the particular dextransucrase. Glucansucrases that catalyze glucans synthesis from sucrose. When other carbohydrates, in addition to sucrose, are present in the enzyme digest, the enzyme transfers glucose to the carbohydrate acceptors in the secondary reaction that diverts some of the glucose from incorporation into glucan. Many carbohydrate acceptors have been recognized and the products that result are dependent on the particular enzyme and the structure of the particular acceptor. Because of these unique catalytic characteristics, various dextransucrases have many important industrial and medical uses. To improve the understanding of their action mode and extend their applications, this study describes mechanism of glucan synthesis and potential industrial uses of dextransucrases, and our recent findings on the structural, functional organization and directed evolution of the glucansucrases to offer for designing glucansucrases with improved properties.

• Parasites, Hosts and Diseases
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• v.34 no.4
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• pp.279-282
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• 1996

The enzyme-linked immunosorbent assay (ELISA)-inhibition test using a Clonorchis sinensis species-specific mouse monoclonal antibody (MAb) , CsHyb 0605-23, showed increased specificity over the conventional ELISA used for serodiagnosis of clonorchiasis. To characterize the corresponding antigen further, the MAb was tested against polysaccharide, protein and glycolipid fractions obtained from a crude extract of C. slnensis adult worms, using chloroform, methanol and phenol extractions. Only the polysaccharide fraction was recognized by the mb among those fractions. Mild oxidation of the antigen with sodium periodate showed decreased reactivity against the MAb. We concluded that the antigen and antigenic determinants recognized by the MAb are carbohydrates.

• Proceedings of the Korean Society of Life Science Conference
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• 2002.12a
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• pp.13-19
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• 2002

To elucidate the regulatory mechanism for expression of sialyl-glycoconjugates and their biological functions, ninetheen sialyltransferase cDNAs including eleven by our group or co-works have been cloned and characterized so far. The cloned sialyltransferases are classified into four families according to the carbohydrate linkages they synthesize: ${\alpha}2,3-sialyltransferase$ (ST3Gal I-VI), ${\alpha}$ 2,6-sialyltransferase (ST6Gal I), GalNAc ${\alpha}$ 2,6-sialyltransferase (ST6GalNAc I-VI), and ${\alpha}2,8-sialyltransferase$ (ST8Sia I-VI). Each of the sialyltransferase genes is differentially expressed in a tissue-, cell type-, and stage-specific manner. These enzymes differ in their substrate specificity and various biochemical parameters. However, enzymatic analysis conducted in vitro with recombinant enzyme revealed that one linkage can be synthesized by multiple enzymes. We present here an overview of structure and function of sialyltransferases performed by our group and co-works. Genomic structures and transcriptional regulation of two kinds of human sialyltransferase gene are also presented.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.301-304
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• 2012

Objective: To explore the associations of serum tumor associated material (TAM) with other common tumor markers like carcinoembryonic antigen (CEA), carbohydrate antigen 125 (CA125), carbohydrate antigen19-9 (CA19-9) and its clinical application in non-small cell lung cancer (NSCLC) patients. Methods: A total of 87 patients were enrolled into this study, all with histologically or cytologically confirmed NSCLC. With the method of chemical colorimetry, the level of TAM was determined and compared, while chemiluminescence was used to measure the levels of common tumor markers. Results: The level of TAM decreased after chemotherapy compared with before chemotherapy when CT or MRI scans showed disease control. Furthermore, it increased when disease progessed and there was no statistically significant difference in monitoring of TAM and common tumor markers (P>0.05). Conclusions: Detecting TAM in NSCLC patients has a higher sensitivity and specificity, so it can be used as an indicator for clinical monitoring of lung cancer chemotherapy.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.8
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• pp.3425-3428
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• 2015

Objective: To explore the association of serum tumor abnormal protein (TAP) with other serological biomarkers e.g. carcinoembryonic antigen (CEA), carbohydrate antigen 125 (CA125), carbohydrate antigen 19-9 (CA19-9) and its clinical application in colorectal cancer (CRC) patients. Methods: Patients (N=98) were enrolled into this study with histologically or cytologically confirmed CRC. Using a test kit, the level of TAP was determined, while chemiluminescence was used to measure the levels of some other common serological biomarkers e.g. CEA, CA125 and CA19-9. Results: The area of TAP condensed particulate matter decreased after chemotherapy compared with before chemotherapy when CT or MRI scans showed disease control. In contrast, it increased with disease progression (P<0.05). Furthermore, a statistically significant difference was confirmed in monitoring of TAP and common serological biomarkers e.g. CEA and CA19-9 (p<0.05). Conclusions: Detecting TAP in CRC patients has high sensitivity and specificity and can be used as a new independent indicator for clinically monitoring CRC patients in the course of chemotherapy.

• Korean Journal of Veterinary Research
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• v.37 no.3
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• pp.547-554
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• 1997

Galectin-3 is known as an animal ${\beta}$-galactoside-binding lectin charicterized with S-type carbohydrate recognition domain. It plays a role in growth, adherence and movement of cells. It is, also, related to the cell transformation and metastasis of tumor cells. In this study, we have expressed and purified recombinant human galectin-3 (rHgalectin-3) using E coli system and asialofetuin affinity chromatography for the future development of monoclonal antibody to Hgalectin-3, which is suggested as the tumor marker for the gastric and thyroid gland cancers. Expressed protein was confirmed as the Hgalectin-3 by immunoblot with cross-reactive murine monoclonal antibody. Lectin activity and specificity of purified protein were, also, confirmed by the competitive inhibition with galectin-3 specific carbohydrate, lactose. Like physiological galectin-3, lectin activity of the molecule was not changed in nonreduced condition. Dimer formation, furthermore, was observed at high concentration of the protein even in the reduced condition, which is well known in physiological galectin-3. These results showed purified rHgalectin-3 has the same activity and molecular nature compared to the physiological galectin-3.

• Journal of Gastric Cancer
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• v.14 no.4
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• pp.221-228
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• 2014

Purpose: This study aimed to evaluate the value of serum carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) levels to detect gastric cancer recurrence. Materials and Methods: We retrospectively reviewed 154 patients who developed recurrence within 2 years after curative gastric cancer surgery and analyzed the relationship between postoperative CEA and CA19-9 levels and recurrence. We readjusted the cut-off values to improve the detection of recurrence. Subgroup analysis according to clinicopathologic variables was performed to further investigate the relationship between recurrence and CEA and CA19-9 levels. Results: The sensitivity and specificity for elevated CEA levels to detect recurrence were 40.6% and 89.5%, respectively, and those for CA19-9 were 34.2% and 93.6%, respectively. The sensitivity and specificity for elevation of either tumor marker were 54.3% and 84.0%, respectively; those for elevation of both tumor markers were 19.2% and 98.4%, respectively. By readjusting the cut-off values from 5.0 ng/ml to 5.2 ng/ml for CEA and from 37.00 U/ml to 30.0 U/ml for CA19-9, the sensitivity was increased from 34.2% to 40.2% for CA19-9, while there was no increase in sensitivity for CEA. In subgroup analysis, the sensitivity of CEA was higher in patients with elevated preoperative CEA levels than in patients with normal preoperative CEA levels (86.7% versus 33.7%; P<0.001). Furthermore, the sensitivity of CA19-9 was higher in patients with elevated preoperative CA19-9 levels than in patients with normal preoperative CA19-9 levels (82.61% versus 26.83%; P<0.001). Conclusions: CEA and/or CA19-9 measurement with the readjusted cut-off values allows for more effective detection of gastric cancer recurrence.