• Reproductive and Developmental Biology
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• v.36 no.1
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• pp.39-47
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• 2012

Ovarian cancer is the most lethal gynecological malignancy, and specific biomarkers are important needed to improve diagnosis, prognosis, and to forecast and monitor treatment efficiency. There are a lot of pathological factors, including reactive oxygen species (ROS), involved in the process of cancer initiation and progression. The oxidative modification of proteins by ROS is implicated in the etiology or progression of disorders and diseases. In this study, a labeling experiment with the thiol-modifying reagent biotinylated iodoacetamide (BIAM) revealed that a variety of proteins were differentially oxidized between normal and tumor tissues of ovarian cancer patients. To identify cysteine oxidation-sensitive proteins in ovarian cancer patients, we performed comparative analysis by nano-UPLC-$MS^E$ shotgun proteomics. We found oxidation-sensitive 22 proteins from 41 peptides containing cysteine oxidation. Using Ingenuity program, these proteins identified were established with canonical network related to cytoskeletal network, cellular organization and maintenance, and metabolism. Among oxidation-sensitive proteins, the modification pattern of Collagen alpha-1(VI) chain (COL6A1) was firstly confirmed between normal and tumor tissues of patients by 2-DE western blotting. This result suggested that COL6A1 might have cysteine oxidative modification in tumor tissue of ovarian cancer patients.

• Journal of Life Science
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• v.11 no.5
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• pp.415-422
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• 2001

Many secreted proteins have disulfide bonds that are important for their structure and function. Protein disulfide isomerase (PDI, EC 5.3.1.4.), an enzyme that catalyzes the formation and rearrangement of thiol/disulfide exchange reactions, is a resident of the endoplasmic reticulum (ER). The subcellular localization and its function as catalyst of disulfide bond formation in the biosynthesis of secretory and cell membrane proteins suggest that PDI plays a key role in the secretory pathway. We have isolated a cDNA encoding protein disulfide isomerase from Bombyx mori(bPDI). It has been characterized under ER stress conditions (dominantly induced by calcium ionophore A23187, tunicamycin and DTT), which is known to cause an accumulation of unfolded proteins in the ER. Furthermore, It has also been examined for tissue distribution(pronounced at the fat body), hormonal regulation (juvenile hormone, insulin and juvenile +transferrin; however, it is not effected by transferrin alone), and the effect of exogenous bacteria (peak at 16 h after infection) on the bPDI mRNA expression. The results suggest that bPDI is a member of the ER stress protein group, and it may play an important role in exogenous bacterial infection in fat body, and that homones regulate its expression.

• Food Science of Animal Resources
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• v.37 no.1
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• pp.114-122
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• 2017

This study was conducted to evaluate the effects of clove extract (CE) (0.25%, 0.5%, 1%, and 2%) on the oxidative stability and quality deterioration of Chinese-style sausage stored for 21 d at $4^{\circ}C$. The addition of clove extract to sausages significantly retarded increases in Thiobarbituric Reactive Substances (TBARS) values (p<0.05), while also controlling the production of protein carbonyls (p<0.05). However, the addition of clove extract promoted reduced thiol group content in sausages (p<0.05). Sausages amended with clove extract also had decreased $L^*$ values (p<0.05) and increased $a^*$ values (p<0.05) when compared with the control. Similarly, texture deterioration was retarded in sausage containing added clove extract when compared with the control during refrigerated storage. Moreover, the addition of clove extract had no negative effects on the sensory properties of sausages. These results suggested that clove extract was effective at protecting sausages from oxidation and quality deterioration during refrigerated storage for 21 d.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.403-406
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• 2002

Molecular self-assembled of surfactant viologen are of recent interest because they can from functional electroeds as well as micellar assemblies. which can be profitably utilized for display devices. photoelectrochemical studies and electrocatalysis as electron acceptor or electron mediator[1-3]. Fromherz et al studied the se1f-assembly of thiol and disulfide derivatives of viologens bearing long n-alkyl chains on Au electrode surface[4]. In this study, the electrochemical behavior of self-assembled viologen monolayer has been investigated with QCM, which has been known as nano-gram order mass detector. The self-assembly process of viologen was monitored using resonant frequency$({\Delta}F)$ and resonant resistance(R). The redox process of viologen was observed with resonant frequency$({\Delta}F)$.

• The Journal of Natural Sciences
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• v.8 no.2
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• pp.57-61
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• 1996

The $\beta$-glucosidase enzyme was purified from E. coli carrying Cellulomonas fimi $\beta$-glucosidase gene. SDS-PAGE and analytical gel filtration revealed that molecular weight of this enzyme was 56,000 dalton and consisted of a single polypeptide.Inhibition caused by heavy metals and activation by dithiothreitol suggest the existence of essential thiol group in the enzyme. The enzyme was not active on maltose (glucose $\alpha$-1,4-glucose) which has a $\alpha$-linkage, whereas it was active on lactose (glucose $\beta$-1,4-glucose), PNPG (p-nitrophenyl $\beta$-D-glucopyranoside) and PNPC (p-nitrophenyl $\beta$-D-cellobioside), although its reaction rates were different.

• Archives of Pharmacal Research
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• v.27 no.12
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• pp.1275-1283
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• 2004

Fate of the nascent thyrolglobulin (Tg) molecule is characterized by multimerization. To establish the formation of Tg multimers, the partially unfolded/reduced Tg or deoxycholate-treated/ reduced Tg was subjected to protein disulfide isomerase (PDI)-mediated multimerization. Oxidized glutathione/PDI-mediated formation of multimeric Tg forms, requiring at least an equivalent molar ratio of PDI/Tg monomer, decreased with increasing concentration of reduced glutathione (GSH), suggesting the oxidizing role of PDI. Additional support was obtained when PDI alone, at a PDI/Tg molar ratio of 0.3, expressed a rapid multimerization. Independently, the exposure of partially unfolded Tg to GSH resulted in Tg multimerization, enhanced by PDI, according to thiol-disulfide exchange. Though to a lower extent, a similar result was observed with the dimerization of deoxycholate-pretreated Tg monomer. Consequently, it is implied that intermolecular disulfide linkage may be facilitated at a limited region of unfolded Tg. In an attempt to examine the multimerization site, the cysteine residue-rich fragments of the Tg were subjected to GSH-induced multimerization; a 50 kDa fragment, containing three vicinal dithiols, was multimerized, while an N-terminal domain was not. Present results suggest that the oxidase as well as isomerase function of PDI may be involved in the multimerization of partially unfolded Tg or deoxycholate-treated Tg.

• Bulletin of the Korean Chemical Society
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• v.33 no.1
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• pp.100-104
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• 2012

Thrombin is a serine protease that catalyzes the conversion of soluble fibrinogen to insoluble fibrin, and thus induces physiological and pathological blood coagulation. Therefore, it is important to detect thrombin in blood serum for purposes of diagnosis. To achieve this goal, it has been suggested that a 15-mer aptamer strongly binds with thrombin to form a G-quartet structure of the aptamer. Generally, 5'-end thiol-functionalized aptamer has been used as an anti-thrombin binder. Herein, we evaluate the possibility of utilizing a 3'-SH aptasensor for thrombin detection using SPR spectroscopy, and compare the enhancement of the electrochemical signal of the thrombin-aptamer bound on a porous gold substrate. Although the two aptamers have similar configurations, in SPR analysis, the 3'-SH aptamer was a effective aptasensor as well as 5'-SH aptamer. Results from electrochemical analysis showed that the porous gold substrate acted as a good substrate for an aptasensor and demonstrated 5-fold enhancement of current change, as compared to gold thin film.

• Bulletin of the Korean Chemical Society
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• v.34 no.11
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• pp.3233-3238
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• 2013

Two new Cu(II) complexes, $[Cu_2(acpy-mdtc)_2(HBA)(ClO_4)]{\cdot}H_2O$ (1) (acpy-mdtc- = 2-acetylpyridine S-methyldithiocarbamate and $HBA^-$ = benzilic acid anion) and $[Cu_2(acpy-phtsc)_2(HBA)]{\cdot}ClO_4$ (2) (acpy-$phtsc^-$ = 2-acetylpyridine 4-phenyl-3-thiosemicarbazate) have been synthesized and characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis, and single crystal X-ray diffraction. The X-ray analysis reveals that the structures of 1 and 2 are dinuclear copper(II) complexes bridged by two thiolate sulfur atoms of Schiff base ligand and bidentate bridging $HBA^-$ anion. For 1, each of the two copper atoms has different coordination environments. Cu1 adopts a five-coordinate square-pyramidal with a $N_2OS_2$ donor, while Cu2 exhibits a distorted octahedral geometry in a $N_2O_2S_2$ manner. For 2, two Cu(II) ions all have a five-coordinate square-pyramidal with a $N_2OS_2$ donor. In each complex, the Schiff base ligand is coordinated to copper ions as a tridentate thiol mode.

• Journal of the Korean Chemical Society
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• v.25 no.6
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• pp.390-393
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• 1981

Eight new compounds were prepared by the addition reaction of thioglycolic acid to ${\beta}$-nitrostyrene and its derivatives. s-[2-Nitro-1-phenylethyl]-thioglycolic acid; s-[2-nitro-1-(p-methyl)phenylethyl]-thioglycolic acid; s-[2-nitro-1-(p-methoxy)phenylethyl]-thioglycolic acid; s-[2-nitro-1-(p-chloro)phenylethyl]-thioglycolic acid; s-[2-nitro-1-(p-bromo)phenylethyl]-thioglycolic acid; s-[2-nitro-1-(p-nitro)phenylethyl]-thioglycolic acid; s-[2-nitro-1-(3-methoxy-4-ethoxy)phenylethyl]-thioglycolic acid; s-[2-nitro-1-(3,4,5-trimethoxy)phenylethyl]-thioglycolic acid; The structure of these compound were identified by elemental analysis, UV, IR and NMR spectral data.

• Bulletin of the Korean Chemical Society
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• v.35 no.2
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• pp.383-391
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• 2014

Biotin-S-S-Phosphine was designed and synthesized as a potential tool for a proteomic study of O-GlcNAcmodified proteins. This reagent features a disulfide linker between a triarylphosphine moiety, which allows selective conjugation to azide-containing proteins, and a biotin moiety that can allow easy isolation through its strong affinity toward avidin-coated solid beads. The disulfide linkage within this reagent can allow the easy release of the bound molecules of interest, which is difficult to achieve when a biotin:avidin pair is used alone, by reducing the disulfide bond of the reagent with DTT. Preliminary in vitro biological assays with azidelabeled and unlabeled cell lysates and a pure protein Nup62 showed that the Biotin-S-S-Phosphine reagent is highly reactive toward the free thiol groups of proteins. When a molecular tool with a disulfide linker is applied to the enrichment of the molecules of interest from other species, it is important to block the free-thiols of the sample using exhaustive alkylation prior to the Staudinger ligation reactions to restore the bioorthogonal nature of this reaction.