Arnhold Jürgen, Malle Ernst
Medical Faculty, Institute of Medical Physics and Biophysics, Leipzig University, 04107 Leipzig, Germany.
Gottfried Schatz Research Center, Division of Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria.
Antioxidants (Basel). 2022 Apr 30;11(5):890. doi: 10.3390/antiox11050890.
Mammalian heme peroxidases are fascinating due to their unique peculiarity of oxidizing (pseudo)halides under physiologically relevant conditions. These proteins are able either to incorporate oxidized halides into substrates adjacent to the active site or to generate different oxidized (pseudo)halogenated species, which can take part in multiple (pseudo)halogenation and oxidation reactions with cell and tissue constituents. The present article reviews basic biochemical and redox mechanisms of (pseudo)halogenation activity as well as the physiological role of heme peroxidases. Thyroid peroxidase and peroxidasin are key enzymes for thyroid hormone synthesis and the formation of functional cross-links in collagen IV during basement membrane formation. Special attention is directed to the properties, enzymatic mechanisms, and resulting (pseudo)halogenated products of the immunologically relevant proteins such as myeloperoxidase, eosinophil peroxidase, and lactoperoxidase. The potential role of the (pseudo)halogenated products (hypochlorous acid, hypobromous acid, hypothiocyanite, and cyanate) of these three heme peroxidases is further discussed.
哺乳动物血红素过氧化物酶因其在生理相关条件下氧化（拟）卤化物的独特特性而引人关注。这些蛋白质既能将氧化的卤化物掺入活性位点附近的底物中，也能生成不同的氧化（拟）卤化物种，这些物种可参与与细胞和组织成分的多种（拟）卤化和氧化反应。本文综述了（拟）卤化活性的基本生化和氧化还原机制以及血红素过氧化物酶的生理作用。甲状腺过氧化物酶和过氧化物酶是甲状腺激素合成以及基底膜形成过程中胶原蛋白IV功能性交联形成的关键酶。特别关注了免疫相关蛋白如髓过氧化物酶、嗜酸性粒细胞过氧化物酶和乳过氧化物酶的性质、酶促机制以及由此产生的（拟）卤化产物。进一步讨论了这三种血红素过氧化物酶的（拟）卤化产物（次氯酸、次溴酸、次硫氰酸盐和氰酸盐）的潜在作用。
