雷纳酶是一种α-NAD(P) H氧化酶/异酶
Brett A Beaupre1, Brenton R Carmichael, Matthew R Hoag
1Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee , 3210 N. Cramer Street, Milwaukee, Wisconsin 53211-3209, United States.
Journal of the American Chemical Society
|August 23, 2013
概括
脏分泌的荷尔蒙雷纳酶被确定为α-NAD(P) H氧化酶/无氧化酶,而不是单胺氧化酶. 这种新型的酶活性涉及催化表皮化反应,这是哺乳动物生理学上的第一次.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 生理学 生理学 生理学
背景情况:
- 雷纳酶是一种分泌的蛋白质激素,会影响血压和心率.
- 它作为一种单胺氧化酶C的作用,氧化类甲醇胺,缺乏体外证据.
- 雷纳酶的结构类似于氧化酶,但具有独特的活性位点.
研究的目的:
- 为了阐明酶的真正催化功能.
- 为了在体外研究雷纳酶的酶活性.
- 确定雷纳酶的基质和反应机制.
主要方法:
- 雷纳酶的酶活性的表征.
- 研究辅助因子的要求和反应产物.
- 催化过程的动态分析.
主要成果:
- 雷纳酶作为α-NAD(P) H氧化酶/异质酶起作用.
- 它利用低度的NADPH和NADH的α-异构体.
- 该酶迅速降低其黄素辅因子,与二氧化物反应,产生过氧化,并对尼古丁胺二核酸进行表化.
结论:
- 雷纳酶的主要功能不是单胺氧化酶活性.
- 这项研究揭示了一种新的黄蛋白活性:催化了表皮化反应.
- 这些发现突显了自然发生的α-NAD(P) H异常的生理意义.
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