Oxygen plays a crucial role in the metabolism of non-anaerobic organisms. However, understanding the detailed process of how triplet oxygen participates in the enzymatic oxidation of organic compounds involved in life processes is still lacked. Noteworthy, recent studies have found that cofactor-free oxidases- and oxygenases-catalyzed activation of oxygen through the proton-coupled electron transfer (PCET), which is significantly different from the previously proposed single electron transfer (SET) mechanism. Herein, we have summarized recent advances in the general mechanism of catalytic activation reactions of triplet oxygen by these enzymes. We believe that this review not only helps people deeply understand the metabolic processes involved in oxygen in organisms, but also provides valuable theoretical reference data for designing more efficient enzyme mutants for treating diseases and handling environmental pollution in the future.

中文翻译：

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揭示无辅因子氧化酶和加氧酶催化的氧活化中的质子耦合电子转移：理论观点


氧气在非厌氧生物的新陈代谢中起着至关重要的作用。然而，仍然缺乏了解三重态氧如何参与生命过程中涉及的有机化合物的酶促氧化的详细过程。值得注意的是，最近的研究发现，无辅因子的氧化酶和加氧酶通过质子耦合电子转移 （PCET） 催化氧的活化，这与以前提出的单电子转移 （SET） 机制有很大不同。在此，我们总结了这些酶催化三重态氧发生催化活化反应的一般机制的最新进展。我们相信，本文不仅有助于人们深入了解生物体内氧所涉及的代谢过程，而且为未来设计更高效的酶突变体来治疗疾病和处理环境污染提供了有价值的理论参考数据。