• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2005년도 제5회 발생공학 국제심포지엄 및 학술대회
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• pp.41-41
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• 2005

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2002년도 춘계학술발표대회 발표논문초록집
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• pp.64-64
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• 2002

Peroxiredoxins (Prxs) possess protective activity against oxygen radicals generated by thiol-catalyzed oxidative systems. We already reported the genomic structure and its expression of mouse Prx Ⅰ, Ⅱ, and 1-Cys Prx. However, the Prx Ⅲ has not been determined. That was initially defined transiently expressed gene, mouse MER5, of murine erythroleukaemia cell differentiation. In addition, this protein was recently redefined a member of the thiol-specific antioxidant gene family. (omitted)

• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 2005년도 제5회 발생공학 국제심포지엄 및 학술대회
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• pp.41-41
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• 2005

• Genomics & Informatics
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• 제3권2호
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• pp.55-60
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• 2005

Peroxiredoxins (Prx's) are a superfamily of peroxidases that are ubiquitous in all super-kingdoms. Previous biochemical and structural studies have suggested that Prx's could be divided into five subfamilies (1-Cys, Typical 2-Cys, Atypical 2-Cys C-, L- and R- types). In this work, we have developed a set of regular expression patterns describing subfamily-specific spatial constraints of the key catalytic residues. Using these patterns, 1,016 Prx's available in public databases were classified into the five subfamilies. Our method performed well for most of the types except for Atypical 2 Cys R type.

• Molecules and Cells
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• 제39권1호
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• pp.20-25
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• 2016

Photosynthesis is a highly robust process allowing for rapid adjustment to changing environmental conditions. The efficient acclimation depends on balanced redox metabolism and control of reactive oxygen species release which triggers signaling cascades and potentially detrimental oxidation reactions. Thiol peroxidases of the peroxiredoxin and glutathione peroxidase type, and ascorbate peroxidases are the main peroxide detoxifying enzymes of the chloroplast. They use different electron donors and are linked to distinct redox networks. In addition, the peroxiredoxins serve functions in redox regulation and retrograde signaling. The complexity of plastid peroxidases is discussed in context of suborganellar localization, substrate preference, metabolic coupling, protein abundance, activity regulation, interactions, signaling functions, and the conditional requirement for high antioxidant capacity. Thus the review provides an opinion on the advantage of linking detoxification of peroxides to different enzymatic systems and implementing mechanisms for their inactivation to enforce signal propagation within and from the chloroplast.

• Molecules and Cells
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• 제39권1호
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• pp.26-30
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• 2016

Peroxiredoxins are ubiquitous thiol proteins that catalyse the breakdown of peroxides and regulate redox activity in the cell. Kinetic analysis of their reactions is required in order to identify substrate preferences, to understand how molecular structure affects activity and to establish their physiological functions. Various approaches can be taken, including the measurement of rates of individual steps in the reaction pathway by stopped flow or competitive kinetics, classical enzymatic analysis and measurement of peroxidase activity. Each methodology has its strengths and they can often give complementary information. However, it is important to understand the experimental conditions of the assay so as to interpret correctly what parameter is being measured. This brief review discusses different kinetic approaches and the information that can be obtained from them.

• Molecules and Cells
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• 제39권1호
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• pp.1-5
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• 2016

Peroxiredoxins (Prxs) are a very large and highly conserved family of peroxidases that reduce peroxides, with a conserved cysteine residue, designated the "peroxidatic" Cys ($C_P$) serving as the site of oxidation by peroxides (Hall et al., 2011; Rhee et al., 2012). Peroxides oxidize the $C_P$-SH to cysteine sulfenic acid ($C_P$-SOH), which then reacts with another cysteine residue, named the "resolving" Cys ($C_R$) to form a disulfide that is subsequently reduced by an appropriate electron donor to complete a catalytic cycle. This overview summarizes the status of studies on Prxs and relates the following 10 minireviews.

• Tuberculosis and Respiratory Diseases
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• 제58권1호
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• pp.31-42
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• 2005

배 경 : peroxiredoxins는 거의 모든 생명체에 공통적으로 보존되어 있으며, 최근에 발견된, 특이한 peroxidases로 인체에서 6가지 동위효소가 알려져 있으며, 산화스트레스에 대한 방어역할을 담당하고, $H_2O_2$신호전달 과정에서 중요한 조절 역할을 한다. peroxiredoxin은 $H_2O_2$ 처리 과정 중에서 자신이 산화되어 불활성화 되는데, 산화된 후 다시 재생되는 것으로 보고되나 그 생리적은 의미는 분명하지 않다. 이에 저자들을 폐상 피세포주, 대식세포주, 폐포모세혈관 내피세포주 및 기타 섬유모세포주 들에서 $H_2O_2$ 에 의한 Prx의 산화과정과 재생을 알아보고자 하였다. 방 법 : 수술 환자에서 적출한 정상 폐조직과, 세포주로는 평상시 산화 스트레스에 노출이 많을 것으로 예상되는 세포들로써, 폐포상피세포의 I 형 및 II 형 세포에서 기원한 A549, WI 26, Raw 264.7, Rat2,및 폐포 모세혈관 내피세포주 등을 이용하여 이를 $50{\mu}M$. $100{\mu}M$, $500{\mu}M$ 의 $H_2O_2$로 산화시켜 불활성화 한 후, 추적관찰 하였으며, 시간대 별로(0. 10, 30, 60, 120, 240, 480 분) 수확하여, 이를 1차원 non-reducing SDS-PAGE 및 2차원 전기영동로 분리 후, silver stain 과 Western blot으로 분석 하였다. 결 과 : 1. 실험에 사용된 모든 세포주에서, $H_2O_2$ 농도에 비례하여 peroxiredoxin I, II, III 의 불활성화를 관찰할 수 있었고, 10분에 최고로 불활성화되었다. 2. 산화된 이후, 30분경부터 peroxiredoxin 의 재생이 관찰되기 시작 하였으며, 2시간 이후부터 확연하였다. 3. 다시 재생된 peroxiredoxin은 $H_2O_2$투여로서, 다시 불활성화되어, 재생된 Prx 가 활성을 지닌 단백질임을 알 수 있었다. 4. 재생의 속도는 사용된 세포주마다 차이가 있었으며 (A549 >Raw 264.7 >$Rat_2$ >WI26), 단백질 합성억제제인 cycloheximide ($10{\mu}g/ml$) 존재 하에서도 변함 없이 관찰되었다. 결 론 : 세포 내에는 산화되어 불활성화된 peroxiredoxin을 재생하는 체계가 존재 하며, 이는 활성부위 cysteine을 갖는 다른 단백질에도 공통적으로 적용될 수 있는 분자 스위치일 가능성이 높으며, 산화에 의한 신호전달과정이나, 질병 모델에서 Prx 단백의 재생 체계의 이상과 병인에 관한 추가적인 연구가 필요할 것으로 사료된다.

• Mass Spectrometry Letters
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• 제3권1호
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• pp.10-14
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• 2012

Artificially oxidized cysteine residues in peroxiredoxin 6 (Prx6) were detected by electrospray interface capillary liquid chromatography-linear ion trap mass spectrometry after the preparation of two-dimensional gel electrophoresis (2D-GE). We used Prx6 as a model protein because it possesses only two cysteine residues at the 47th and 91st positions. The spot of Prx6 on 2D-GE undergoes a basic (isoelectric point, pI 6.6) to acidic (pI 6.2) shift by exposure to peroxide due to selective overoxidation of the active-site cysteine Cys-47 but not of Cys-91. However, we detected a tryptic peptide containing cysteine sulfonic acid at the 47th position from the basic spot and a peptide containing both oxidized Cys-47 and oxidized Cys-91 from the acidic spot of Prx6 after the separation by 2D-GE. We prepared two types of oxidized Prx6s: carrying oxidized Cys-47 (single oxidized Prx6), and other carrying both oxidized Cys-47 and Cys-91 (double oxidized Prx6). Using these oxidized Prx6s, the single oxidized Prx6 and double oxidized Prx6 migrated to pIs at 6.2 and 5.9, respectively. These results suggest that oxidized Cys-47 from the basic spot and oxidized Cys-91 from the acidic spot are generated by artificial oxidation during sample handling processes after isoelectric focusing of 2D-GE. Therefore, it is important to make sure of the origin of cysteine oxidation, if it is physiological or artificial, when an oxidized cysteine residue(s) is identified.

• Molecules and Cells
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• 제27권3호
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• pp.279-282
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• 2009

"Two-cysteine" peroxiredoxins are antioxidant enzymes that exert a cytoprotective effect in many models of oxidative stress. However, under highly oxidizing conditions they can be inactivated through hyperoxidation of their peroxidatic active site cysteine residue. Sulfiredoxin can reverse this hyperoxidation, thus reactivating peroxiredoxins. Here we review recent investigations that have shed further light on sulfiredoxin's role and regulation. Studies have revealed sulfiredoxin to be a dynamically regulated gene whose transcription is induced by a variety of signals and stimuli. Sulfiredoxin expression is regulated by the transcription factor AP-1, which mediates its up-regulation by synaptic activity in neurons, resulting in protection against oxidative stress. Furthermore, sulfiredoxin has been identified as a new member of the family of genes regulated by Nuclear factor erythroid 2-related factor (Nrf2) via a conserved cis-acting antioxidant response element (ARE). As such, sulfiredoxin is likely to contribute to the net antioxidative effect of small molecule activators of Nrf2. As discussed here, the proximal AP-1 site of the sulfiredoxin promoter is embedded within the ARE, as is common with Nrf2 target genes. Other recent studies have shown that sulfiredoxin induction via Nrf2 may form an important part of the protective response to oxidative stress in the lung, preventing peroxiredoxin hyperoxidation and, in certain cases, subsequent degradation. We illustrate here that sulfiredoxin can be rapidly induced in vivo by administration of CDDO-TFEA, a synthetic triterpenoid inducer of endogenous Nrf2, which may offer a way of reversing peroxiredoxin hyperoxidation in vivo following chronic or acute oxidative stress.