Superoxide dismutases and superoxide reductases.
Superoxide dismutases and superoxide reductases.
复制标题
DOI：
10.1021/cr4005296
复制
发表时间：
2014-04-09
期刊：
影响因子：
62.1
通讯作者：
Valentine, Joan Selverstone
中科院分区：
文献类型：
--
作者：
Sheng, Yuewei;Abreu, Isabel A.;Cabelli, Diane E.;Maroney, Michael J.;Miller, Anne-Frances;Teixeira, Miguel;Valentine, Joan Selverstone
超氧化物，O2·−，在所有与空气接触的生物体中形成，并且根据其生物背景，它可以作为信号剂，有毒物质或自发分解的无害中间体。其水平在体内受到两种不同类型的酶的限制，即超氧化物还原酶（SOR）和超氧化物歧化酶（SOD）。虽然超氧化物一直是进化的重要因素，但至少35亿年前生命首次出现在地球上时并非如此。当时，早期的生物圈高度还原，缺乏任何显著浓度的双氧（O2），与今天的情况非常不同。因此，很少或没有O2·−，因此没有理由进化SOR或SOD酶。相反，生物O2·−的历史可能始于大约24亿年前，当时生物圈开始经历所谓的“大氧化事件”，这是由蓝藻作为产氧光合作用的产物形成的O2水平增加驱动的转变。[1]地球上氧气的增加导致了现有代谢途径的重塑，并引发了新代谢途径的发展。2它的出现导致了所谓的“活性氧物质”（ROS）的形成，例如超氧化物、过氧化氢和羟基自由基，并且需要抗氧化酶和其他抗氧化系统来保护免受日益严重的氧化损伤生命系统。
Superoxide, O2•−, is formed in all living organisms that come in contact with air, and, depending upon its biological context, it may act as a signaling agent, a toxic species, or a harmless intermediate that decomposes spontaneously. Its levels are limited in vivo by two different types of enzymes, superoxide reductase (SOR) and superoxide dismutase (SOD). Although superoxide has long been an important factor in evolution, it was not so when life first emerged on Earth at least 3.5 billion years ago. At that time, the early biosphere was highly reducing and lacking in any significant concentrations of dioxygen (O2), very different from what it is today. Consequently, there was little or no O2•− and therefore no reason for SOR or SOD enzymes to evolve. Instead, the history of biological O2•− probably commences somewhere around 2.4 billion years ago, when the biosphere started to experience what has been termed the “Great Oxidation Event”, a transformation driven by the increase in O2 levels, formed by cyanobacteria as a product of oxygenic photosynthesis. 1 The rise of O2 on Earth caused a reshaping of existing metabolic pathways, and it triggered the development of new ones. 2 Its appearance led to the formation of the so-called “reactive oxygen species”(ROS), for example, superoxide, hydrogen peroxide, and hydroxyl radical, and to a need for antioxidant enzymes and other antioxidant systems to protect against the growing levels of oxidative damage to living systems.
登录
查看更多内容
影响因子：
4.1
作者：
ARUOMA, OI;HALLIWELL, B
通讯作者：
HALLIWELL, B
影响因子：
5.6
作者：
ARCHER, M;HUBER, R;ROMAO, MJ
通讯作者：
ROMAO, MJ
影响因子：
3.6
作者：
Abreu, IA;Saraiva, LM;Teixeira, M
通讯作者：
Teixeira, M
影响因子：
3.3
作者：
Abreu, IA;Rodriguez, JA;Cabelli, DE
通讯作者：
Cabelli, DE
影响因子：
6.5
作者：
Anisimova, Maria;Gascuel, Olivier
通讯作者：
Gascuel, Olivier