• BMB Reports
• /
• 제29권3호
• /
• pp.236-240
• /
• 1996

A 23-kDa molecular mass of antioxidant protein was purified from human liver. This protein exhibited the preventive effect against the inactivation of glutamine synthetase by a metal-catalyzed oxidation system. This antioxidant activity was supported by a thiol-reducing equivalent such as dithiothreitol in a similar manner to that of the 25-kDa thiol-specific antioxidant protein (TSA) from human red blood cells (HR). However, a thioredoxin-linked peroxidase activity of thiol-specific antioxidant protein of human liver (HLTSA) (0.91 ${\mu}mol/min/nmol$ of HLTSA) was much lower than that of thiol-specific antioxidant protein of human red blood cells (HRTSA) (16.4 ${\mu}mol/min/nmol$ of HRTSA). This HLTSA is also immnologically distinct from HRTSA Amino acid sequences of the three tryptic peptides (P1, P2, P3) of HLTSA were found to be completely homologous to segments of the known Mer5-like protein, which belongs to the known TSA family.

• 자연과학논문집
• /
• 제14권2호
• /
• pp.55-65
• /
• 2004

지렁이(Earthworm, Lumbricus terrestris)로부터 thiol-specific antioxidant activity(TSA)를 나타내는 향산화 단백을 분리정제 하였다. 이 향산화 단백은 환원제로 thiol성분에 의해 유지되는 비효소적 금속 촉매 산화계 (MCO, $Fe^{3+}$, DTT 또는 2-mercatoethanol ; Thiol- MCO system)에 의하여 Glutamine Synthetase의 불활성을 억제하지만 아스코르브산과 같은 nonthiol 환원제를 가진 효소적 금속 촉매 산화계 (MCO, $Fe^{3+}$, ascorbate ; nonthiol- MCO system)에서는 Glutamine Synthetase의 불활성을 방어하지 못하였다. 정제된 지렁이 TSA 단백질은 SAS-PAGE에 의해 51-kDa임을 밝혔고, 기존에 알려진 TSA protein과 분자량이 다른 TSA Family로써 활성 산소종에 의한 산화적 손상을 방어하는 향산화 효소로써의 중요한 생화학적 역할을 수행함을 제시하였다.

• 자연과학논문집
• /
• 제14권2호
• /
• pp.67-82
• /
• 2004

고염에서 자라는 원시 박테리아인 Halococcus agglomeratus에서 Thiol-specific antioxidant 활성을 보이는 분자량이 22-kDa인 향산화 단백질을 순수 분리 정제하여 향산화 활성의 특성을 조사하였다. 그 결과 진핵 세포의 Thiol-specific antioxidant protein (TSA of TPx)과 유사한 활성을 갖는 것을 확인 할 수 있었다. 정제된 Thiol-specific antioxidant protein 은 환원제로 thiol 성분을 갖는 비효소적 금속 촉매 산화계( $Fe^{3+}$, $O^2$, DTT 또는 2-mercatoethanol : thiol- MCO system)에 의하여 Glutamine Synthetase (GS)의 불활성화를 방어하고 Ascorbate 같은 nonthiol 성환원제를 갖는 금속 촉매 산화계 ( $Fe^{3+}$, $O^2$, Ascorbatenol: nonthiol- MCO system)에 의해서는 GS의 불활성화를 방어하지 못하였다. 이것은 환원형 thiol성분이 항산화 단백질의 항산화 활성에 전자 공여체로 요구되어 지기 때문이라고 판단된다. 이 단백질은 다른 TPx와는 다르게 100%의 활성을 나타내려면 NaCl의 농도가 500mM이상이 되어야 한다. 이상의 결과는 원시 박테리아에도 TPx가 존재하여 활성 산소종을 제거하는 생화학적 역할을 수행함을 시사하고 있다.

• 자연과학논문집
• /
• 제4권
• /
• pp.1-10
• /
• 1991

발현 Vector인 pKK223-3를 이용하여 효모 Thiol-Specific Antioxidant단백질 유전자를 대장균에 도입시켜 이 단백질을 발현시켰다. 이 단백질은 대장균 단백질의 약 1% 정도로 발현되었으며, 물리 및 화학적 특성은 효모의 것과 동일한 특성을 보였다.

• 한국미생물·생명공학회지
• /
• 제18권5호
• /
• pp.501-505
• /
• 1990

토양으로부터 분리한 Streptomyces 속 세균 KIS 13은 thiol 계통 단백질분해효소 활성을 특이적으로 저해하는 저분저량 저해물질을 생성하였다. 저해물질 생성은 세균체성장에 연관된 생성양상이 나타내었다. 배양액으로부토 butanol 추출, silicagel 60 column chromatography, Sephadex LH-2 gel-filtration chromatography, preparative HPLC 등의 과정을 통하여 단백질 분해효소 저해물질을 순수분리하였다. 이 저해물질은 Hammersten casein을 기질로 사용할때, papain에 대하여 non-competitive한 저해양상을 나타내었다.

• 한국생물물리학회:학술대회논문집
• /
• 한국생물물리학회 1997년도 학술발표회
• /
• pp.15-15
• /
• 1997

Recent studies indicate that hydrogen peroxide (H$_2$O$_2$), which is one of the reactive oxygen species involved in the oxidative stress, is an intracellular secondary messenger in the signal transduction. A novel family of thiol specific antioxidant (TSA) enzymes with a peroxidase activity shows no sequence homology to previously known antioxidant enzymes.(omitted)

• Bulletin of the Korean Chemical Society
• /
• 제24권10호
• /
• pp.1512-1514
• /
• 2003

• 대한방사성의약품학회지
• /
• 제4권2호
• /
• pp.85-89
• /
• 2018

We demonstrate a detail protocol for the radiosynthesis of an $^{125}I$-labeled MSTP prosthetic group and its application to the efficient radiolabeling of human serum albumin (HSA). Radioiodination of the precursor (2) was carried out by using $[^{125}I]$NaI and chloramine T as an oxidant at room temperature for 15 min. After HPLC purification of the crude product, the purified $^{125}I$-labeled MSTP ($[^{125}I]1$) was obtained with high radiochemical yield ($73{\pm}5%$, n = 3) and excellent radiochemical purity (>99%). Site-specific reaction between ($[^{125}I]1$) and HSA gave the $^{125}I$-labeled human serum albumin ($[^{125}I]3$) with more than 99% of radiochemical yield as determined by radio-thin-layer chromatography (radio-TLC). These results clearly demonstrate that the present radiolabeling method will be useful for the efficient and convenient radiolabeling of thiol-bearing biomolecules.

• Environmental Engineering Research
• /
• 제20권4호
• /
• pp.342-346
• /
• 2015

Haloacetonitriles (HANs) are nitrogenous disinfection by-products (DBPs) that have been reported to have a higher toxicity than the other groups of DBPs. The adsorption process is mostly used to remove HANs in aqueous solutions. Functionalized composite materials tend to be effective adsorbents due to their hydrophobicity and specific adsorptive mechanism. In this study, the removal of dichloroacetonitrile (DCAN) from tap water by adsorption on thiol-functionalized mesoporous composites made from natural rubber (NR) and hexagonal mesoporous silica (HMS-SH) was investigated. Fourier-transform infrared spectroscopy (FTIR) results revealed that the thiol group of NR/HMS was covered with NR molecules. X-ray diffraction (XRD) analysis indicated an expansion of the hexagonal unit cell. Adsorption kinetic and isotherm models were used to determine the adsorption mechanisms and the experiments revealed that NR/HMS-SH had a higher DCAN adsorption capacity than powered activated carbon (PAC). NR/HMS-SH adsorption reached equilibrium after 12 hours and its adsorption kinetics fit well with a pseudo-second-order model. A linear model was found to fit well with the DCAN adsorption isotherm at a low concentration level.

• BMB Reports
• /
• 제29권6호
• /
• pp.513-518
• /
• 1996

A soluble protein from Saccharomyces cerevisiae specifically provides protection against a thiolcontaining oxidation system but not against an oxidation system without thiol. This 25-kDa protein was thus named thiol-dependent protector protein (TPP). The role of TPP in the cellular defense against oxidative stress was investigated in Escherichia coli containing an expression vector with a yeast genomic DNA fragment that encodes TPP (strain YP) and a mutant in which the catalytically essential amino acid in the active site of TPP (Cys-47) has been replaced with alanine by site-directed mutagenesis (strain YPC47A). There was a distinct difference between these two strains in regard to viability, modulation of activities of superoxide dismutase and catalase, and the oxidative damage of DNA upon exposure to menadione. These results suggest that TPP may play a direct role in the cellular defense against oxidative stress by functioning as an antioxidant protein.