通过用flavohemin复制的肌球蛋白对二氧化物进行降低活性激活
Takashi Matsuo1, Takashi Hayashi, Yoshio Hisaeda
1PRESTO in Japan Science and Technology Corporation (JST).
Journal of the American Chemical Society
|September 19, 2002
概括
肌球蛋白通过将黄素纳入其结构,被改造成一种激活氧的酶. 这种修改后的肌球蛋白显示出增强的氧激活和催化活性,为蛋白质功能化开辟了新的途径.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 蛋白质工程是指蛋白质工程.
背景情况:
- 肌球蛋白是一种储存氧气的血蛋白.
- 已知细胞染色体P450s是氧气激活的血蛋白.
- 肌球蛋白中的原生血红素不促进氧气的激活.
研究的目的:
- 为了将肌球蛋白转化为激活氧气的血蛋白.
- 通过用黄血红蛋白取代其本源的血红蛋白来使肌红蛋白功能化.
- 为了研究复制后的肌球蛋白的催化活性.
主要方法:
- 用人造制造的黄血素复制肌球蛋白.
- 使用ESI-TOF质量,紫外线,光和1H NMR光谱学进行了表征.
- 使用NADH,SOD,catalase和2-phenylpropionaldehyde (2-PPA) 的氧气激活和催化活性的测定.
主要成果:
- 重建的肌球蛋白,rMb(1),已成功地产生和表征.
- rMb(1) 呈现出与原生肌球蛋白相比,氧化血形成的速度快6倍.
- rMb(1) 在2-PPA上表现出变形活性,表明氧化的降解激活到Fe(III) -peroxoanion.
结论:
- 将原生血红素替换为黄血红素成功地将肌球蛋白转化为氧激活酶.
- 弗拉作为一个有效的电子转移中介从NADH到hemin.
- 这项研究提供了第一例由肌球蛋白激活氧气的例子,展示了其功能化潜力.
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