Free radical reduction by thioredoxin reductase at the surface of normal and vitiliginous human keratinocytes.
Free radical reduction by thioredoxin reductase at the surface of normal and vitiliginous human keratinocytes.
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正常和白癜风人角质形成细胞表面的硫氧还蛋白还原酶可减少自由基。
DOI：
10.1111/1523-1747.ep12456848
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
Wood,JM
中科院分区：
文献类型：
--
作者：
Schallreuter,KU;Pittelkow,MR;Wood,JM
人角质形成细胞的细胞培养含有与膜相关的硫氧还蛋白还原酶，该酶在减少外质膜上的自由基方面非常活跃。通过亲和柱层析从人角质形成细胞培养物中纯化该酶，证实了该酶的活性。在自由基底物饱和条件下，以自旋标记季铵化合物为底物，在体内和体外进行酶活性测定。通过监测每单位细胞蛋白的电子自旋共振信号振幅的顺序下降来确定特异性活性。发现以下特性：(1)培养的成体分层细胞的硫氧还蛋白还原酶活性约为新生细胞的两倍。(2)该酶被硫蛋白抑制剂（即副氯环脲-苯甲酸酯和二硝基氯苯）抑制。(3)活性受细胞培养基中钙浓度的调节。在含有2mm Ca++的培养基中，分层角质形成细胞的活性是0.1 mM Ca++浓度的一半。(4)与氧化辅酶NADP+（即NADP+）发生产物抑制。（87%的酶活性抑制超过30分钟）。这种酶在70°C的温度下保持10分钟的热稳定性。在75°C时灭活。比较研究了快速生长的分层分化细胞和未分化细胞的硫氧还蛋白还原酶活性。同时，对从同一供体的白癜风皮肤和正常皮肤分离的角质形成细胞进行酶活性测定。从硫氧还蛋白还原酶的作用机制和代谢活性方面，本研究的结果以及该酶活性与紫外线产生的自由基之间的联系得到了调和。
Cell cultures of human keratinocytes contain membrane-associated thioredoxin reductase that is extremely active in reducing radicals on the outer plasma membrane. This enzyme activity was confirmed by its purification from cultures of stratified human keratinocytes by affinity column chromatography. The enzyme was assayed both in vivo and in vitro using a spin-labeled quaternary ammonium compound as the substrate, under saturating conditions in free radical substrate. Specific activities were determined by monitoring the sequential decrease in the amplitude of the electron spin resonance signal per unit of cell protein. The following properties were found: (1) Cultures of adult stratified cells have approximately twice the thioredoxin reductase activity of neonatal cells. (2) The enzyme is inhibited by thioprotein inhibitors (i.e., parachloromecuri-benzoate and dinitrochlorobenzene). (3) The activity is regulated by calcium concentrations of the cell culture medium. Stratified keratinocytes are half as active in medium containing 2 mM Ca++compared with 0.1 mM Ca++concentration. (4) Product inhibition of the enzyme occurs with oxidized coenzyme NADP+(i.e., 87% inhibition of enzyme activity over 30 min). The enzyme is heat stable at temperatures of 70°C for 10 min. It is inactivated at 75°C. A comparative study of thioredoxin reductase activity on stratified differentiated and undifferentiated rapidly growing cells was performed. Also, enzyme activity was quantitated for cultured keratinocytes isolated from vitiliginous and normal skin of the same donor. The results of this study, and the connection between this enzyme activity and UV-generated free radicals are reconciled in terms of the mechanism of action and metabolic activity of thioredoxin reductase.
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复杂阳离子的致敏性。
DOI：
10.1016/0006-291x(86)90966-6
发表时间：
1986
影响因子：
3.1
作者：
Schallreuter,KU;Wood,JM
通讯作者：
Wood,JM
使用两亲性自旋标记测量膜表面电位。
影响因子：
--
作者：
R. Mehlhorn;L. Packer
通讯作者：
L. Packer
大肠杆菌硫氧还蛋白还原酶的 FAD 和二硫化物还原中的质子化学计量。
影响因子：
4.8
作者：
M. O'Donnell;C. Williams
通讯作者：
C. Williams
人类原角质形成细胞中两种功能不同的生长停滞状态，可调节克隆形成潜力。
DOI：
10.1111/1523-1747.ep12285684
发表时间：
1986
期刊：
The Journal of investigative dermatology
影响因子：
--
作者：
Pittelkow,MR;WilleJr,JJ;Scott,RE
通讯作者：
Scott,RE
还原型硫氧还蛋白还原酶的两个活性位点硫醇与 N-乙基马来酰亚胺的反应。
影响因子：
2.9
作者：
M. O'Donnell;C. Williams
通讯作者：
C. Williams