• Molecules and Cells
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• v.20 no.3
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• pp.339-347
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• 2005

IL-17 (IL-17A or CTLA-8) is the founding member of a novel family of inflammatory cytokines, and emerging evidence indicates that it plays a central role in inflammation and autoimmunity. IL-17 is made primarily, if not exclusively by T cells, but relatively little is known about how its expression is regulated. In the present study, we examined the requirements and mechanisms for IL-17 expression in primary mouse lymphocytes. Like many cytokines, IL-17 is induced rapidly in primary T cells after stimulation of the T cell receptor (TCR) through CD3 crossinking. Surprisingly, however, the pattern of regulation of IL-17 is different in mice than in humans, because "costimulation" of T cells through CD28 only mildly enhanced IL-17 expression, whereas levels of IL-2 were dramatically enhanced. Similarly, several other costimulatory molecules such as ICOS, 4-1BB and CD40L exerted only very weak enhancing effects on IL-17 production. In agreement with other reports, IL-23 enhanced CD3-induced IL-17 expression. However, IL-17 production can occur autonomously in T cells, as neither dendritic cells nor IL-23 were necessary for promoting short-term production of IL-17. Finally, to begin to characterize the TCR-mediated signaling pathway(s) required for IL-17 production, we showed that IL-17 expression is sensitive to cyclosporin-A and MAPK inhibitors, suggesting the involvement of the calcineurin/NFAT and MAPK signaling pathways.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.55-55
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• 2003

P2X$_3$ receptor, a member of P2 purine receptors, is a ligand-gated ion channel activated by extracellular ATP as an endogenous ligand, and highly localized in peripheral and central sensory neurons. The activation of P2X3 receptor by ATP as the pronociceptive effect has been known to initiate the pain signaling involved in chronic inflammatory nociception and neuropathic pain by nerve injury, implicating the possibility of new drug development to control pains. In this study, we have developed a two electrode voltage clamp (TEVC) assay system to evaluate the inhibitory activity of several newly synthesized PPADS and a novel non-ionic antagonist against ATP activation of human P2X3 receptor. PPADS derivatives include several pyridoxine and pyridoxic acid analogs to study the effects of phosphate and aldehyde functional groups in PPADS. All new PPADS analogs were less potent than PPADS at human P2X$_3$ receptors, however, LDD130, a non-ionic analog showed potent antagonistic property with $IC_{50}$/ of 8.34 pM. In order to uncover the structure activity relationships of LDD130, and design new structural analogs, we synthesized and investigated a few structural variants of LDD130, and the results will be discussed in this presentation.

• Food Science and Biotechnology
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• v.18 no.3
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• pp.776-781
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• 2009

A putative cyclomaltodextrinase (BHCD) gene was found from the genome of Bacillus halodurans C-125, which encodes 578 amino acids with a predicted molecular mass of 67,279 Da. It shares 42-59% of amino acid sequence identity with common cyclomaltodextrinase (CDase)-family enzymes. The corresponding gene was cloned by polymerase chain reaction (PCR) and the dimeric enzyme with C-terminal 6-histidines was successfully overproduced and purified from recombinant Escherichia coli. BHCD showed the highest activity against ${\beta}-CD$ at pH 7.0 and $50^{\circ}C$. Due to its versatile hydrolysis and transglycosylation activities, BHCD has been confirmed as a member of CDases. However, BHCD can be distinguished from other typical CDases on the basis of its novel multisubstrate specificity. While typical CDases have over 10 times higher activity on ${\beta}-CD$ than starch or pullulan, the CD-hydrolyzing activity of BHCD is only 2.3 times higher than pullulan. In particular, it showed significantly higher activity ratio of maltotriose to acarbose than other common CDase-family enzymes.

• Journal of Microbiology
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• v.40 no.2
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• pp.109-118
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• 2002

The present work is aimed at providing additional new pure cultures of oxalate utilizing bacteria and its preliminary characterization for further work in the field of oxalate-metabolism and taxonomic studies. The taxonomy of 14 mesophilic, aerobic oxalotrophic bacteria isolated by an enrichment culture technique from soils rhizosphers, and the juice of the petiole/stem tissue of plants was investigated. Isolates were characterized with 95 morphological, biochemical and physiological tests. Cellular lipid components and carotenoids of isolates were also studied as an aid to taxonomic characterization. All isolates were Gram-negative, oxidase and catalase positive and no growth factors were required. In addition to oxalates, some of the strains grow on methanol and/or formate. The taxonomic similarities among isolates, reference strains or previously reported oxalotrophic bacteria were analysed by using the Simple Matching (S/ sub SM/) and Jaccard (S$\_$J/) Coefficients. Clustering was performed by using the unweighted pair group method with arithmetic averages (UPGMA) algorithm. The oxalotrophic strains formed five major and two single-member clusters at the 70-86% similarity level. Based on the numerical taxonomy, isolates were separated into three phenotypic groups. Pink-pigmented strains belonged to Methylobacterium extorquens, yellow-pigmented strains were most similar to Pseudomonas sp. YOx and Xanthobacter autorophicus, and heterogeneous non-pigmented strains were closely related to genera Azospirillum, Ancylobacter, Burkholderia and Pseudomonas. New strains belonged to the genera Pseudomonas, Azospirillum and Ancylobacter that differ taxonomically from other known oxalate oxidizers were obtained. Numerical analysis indicated that some strains of the yellow-pigmented and nonpigmented clusters might represent new species.

• Journal of Microbiology and Biotechnology
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• v.25 no.8
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• pp.1307-1314
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• 2015

Leukemia inhibitory factor (LIF) is a member of the IL-6 cytokine family, having pleiotropic actions such as maintaining stem cell pluripotency and enabling blastocyst implantation. Because the action of LIF is mediated by a ligand-receptor interaction with the LIF receptor (LIF-R), an antagonist for LIF-R has been developed to inhibit LIF-induced signaling. In this study, we present a novel method for the production and purification of an antagonist to human LIF-R (hLA). His-tagged hLA was expressed in E. coli, and simple purification methods without any endopeptidase cleavage were designed. In addition, we determined the optimal temperature conditions for enhancing the production of soluble hLA. Finally, the bioactivity of His-tagged hLA was examined using STAT3 phosphorylation and receptivity of human endometrial ECC-1 cells. Our strategy provides a rapid and efficient method to produce biologically active recombinant hLA.

• Journal of Microbiology and Biotechnology
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• v.18 no.7
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• pp.1203-1206
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• 2008

A Gram-positive strain designated as MSL-$14^T$ isolated from a soil sample collected from Bigeum Island, Korea, was subjected to polyphasic taxonomy. The isolate was strictly aerobic. Cells were short rods and motile. Optimum growth temperature and pH was 28$^{\circ}C$ and 7.0, respectively. It was characterized chemotaxonomically as having a cell-wall peptidoglycan type based on LL-2,6-diaminopimelic acid and MK-$8(H_4)$ as the predominant menaquinone. The major fatty acids were iso-$C_{16:0}$, $C_{17:1}$ omega8c, and $C_{18:1}$ omega9c. The G+C content was 67.6 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain MSL-$14^T$ is affiliated to the genus Nocardioides and formed a distinct lineage within the genus. MSL-$14^T$ showed highest sequence similarity to Nocardioides aestuarii JCM $12125^T$, having a similarity of 96.5%. Based on the 16S rRNA gene sequence divergence and phenotypic characteristics, it is proposed that strain MSL-$14^T$ should be classified as representing a novel member of the genus Nocardioides, for which we propose the name Nocardioides tritolerans sp. novo The type strain is strain MSL-$14^T$ (=KCTC $19289^T$=DSM $19320^T$).

• International Journal of Industrial Entomology and Biomaterials
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• v.14 no.2
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• pp.147-150
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• 2007

Abaecin is a largest member of the proline-rich anti-microbial peptide family found only in the hymenopterans. A cDNA of abaecin was previously isolated and cloned from Bombus ignitus: the mature peptide of Bombus ignitus abaecin was composed of 39 amino acid residues. In the present study, we determined the antibacterial effect of B. ignitus abaecin synthesized at several lengths against several bacteria by radial diffusion assay. The 37-mer peptide (Ab37) inhibited the growth of Gram-negative bacteria Escherichia coli ML-35, Pseudomonas aeruginosa and Salmonela typhimurium, but showed limited inhibitory activity toward Gram-positive bacteria, except for Micrococcus luteus. The truncated 26-mer peptide (Ab26), which was synthesized after truncating some amino acid residues at both N-terminus and C-terminus from the Ab37 peptide, still showed equivalent antibacterial activity to the Ab37. On the other hand, several further truncated peptides exhibited lower activity then did Ab37 peptide.

• Molecules and Cells
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• v.38 no.8
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• pp.723-728
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• 2015

Smurf2, a member of the HECT domain E3 ligase family, is well known for its role as a negative regulator of TGF-${\beta}$ signaling by targeting Smads and TGF-${\beta}$ receptor. However, the regulatory mechanism of Smurf2 has not been elucidated. Arginine methylation is a type of post-translational modification that produces monomethylated or dimethylated arginine residues. In this report, we demonstrated methylation of Smurf2 by PRMT1. In vitro methylation assay showed that Smurf2, not Smurf1, was methylated by PRMT1. Among the type I PRMT family, only PRMT1 showed activity for Smurf2. Transiently expressed Smurf2 was methylated by PRMT1, indicating Smurf2 is a novel substrate of PRMT1. Using deletion constructs, methylation sites were shown to be located within amino acid region 224-298 of Smurf2. In vitro methylation assay following point mutation of putative methylation sites confirmed the presence of Arg232, Arg234, Arg237, and Arg239. Knockdown of PRMT1 resulted in increased Smurf2 expression as well as inhibition of TGF-${\beta}$-mediated reporter activity. Although it is unclear whether or not increased Smurf2 expression can be directly attributed to lack of methylation of arginine residues, our results suggest that methylation by PRMT1 may regulate Smurf2 stability and control TGF-${\beta}$ signaling.

• Molecules and Cells
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• v.28 no.5
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• pp.455-461
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• 2009

Calcineurin is a $Ca^{2+}$/Calmodulin activated Ser/Thr phosphatase that is well conserved from yeast to human. It is composed of catalytic subunit A (CnA) and regulatory subunit B (CnB). C. elegans homolog of CnA and CnB has been annotated to tax-6 and cnb-1, respectively and in vivo function of both genes has been intensively studied. In C. elegans, calcineurin play roles in various signaling pathways such as fertility, movement, body size regulation and serotonin-mediated egg laying. In order to understand additional signaling pathway(s) in which calcineurin functions, we screened for binding proteins of TAX-6 and found a novel binding protein, HLH-11. The HLH-11, a member of basic helix-loop-helix (bHLH) proteins, is a putative counterpart of human AP4 transcription factor. Previously bHLH transcription factors have been implicated to regulate many developmental processes such as cell proliferation and differentiation, sex determination and myogenesis. However, the in vivo function of hlh-11 is largely unknown. Here, we show that hlh-11 is expressed in pharynx, intestine, nerve cords, anal depressor and vuvla muscles where calcineurin is also expressed. Mutant analyses reveal that hlh-11 may have role(s) in regulating body size and reproduction. More interestingly, genetic epistasis suggests that hlh-11 may function to regulate serotoninmediated egg laying at the downstream of tax-6.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.12
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• pp.5303-5307
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• 2016

Objective: Brain tumors cause great mortality and morbidity worldwide, and success rates with surgical treatment remain very low. Several recent studies have focused on introduction of novel effective medical therapeutic approaches. Genistein is a member of the isoflavonoid family which has proved to exert anticancer effects. Here we assessed the effects of genistein on the expression of MMP-2 and VEGF in low and high grade gliomas in vitro. Materials and Methods: High and low grade glioma tumor tissue samples were obtained from a total of 16 patients, washed with PBS, cut into small pieces, digested with collagenase type I and cultured in DMEM containing 10% FBS. When cells reached passage 3, they were exposed to genistein and MMP-2 and VEGF gene transcripts were determined by quantitative real time PCR (qRT-PCR). Results: Expression of MMP-2 demonstrated 580-fold reduction in expression in low grade glioma cells post treatment with genistein compared to untreated cells (P value= 0.05). In cells derived from high grade lesions, expression of MMP-2 was 2-fold lower than in controls (P value> 0.05). Genistein caused a 4.7-fold reduction in VEGF transcript in high grade glioma cells (P value> 0.05) but no effects were evident in low grade glioma cells. Conclusion. Based on the data of the present study, low grade glioma cells appear much more sensitive to genistein and this isoflavone might offer an appropriate therapeutic intervention in these patients. Further investigation of this possibility is clearly warranted.