Department of Pathology, University of Turku, Kiinamyllynkatu 10, FIN-20520 Turku, Finland.
Biochimie. 2010 Jun;92(6):638-44. doi: 10.1016/j.biochi.2010.01.019. Epub 2010 Feb 4.
Peroxiredoxins (Prx) are enzymes that catalyze the reduction of hydrogen peroxide and alkyl hydroperoxides. Prxs are ubiquitous enzymes with representatives found in Bacteria, Archaea and Eukarya. Many 1-cysteine peroxiredoxins (1-CysPrx) are dual-function enzyme with both peroxidase and acidic Ca(2+)-independent phospholipase A(2) (aiPLA(2)) activities. The functions proposed for 1-CysPrx/aiPLA(2) include the protection of cell membrane phospholipids against oxidative damage (peroxidation) and the metabolism (hydrolysis) of phospholipids, such as those of lung surfactant. The peroxidase active site motif PVCTTE of 1-CysPrx contains the conserved catalytic cysteine residue, and the esterase (lipase) motif GXSXG of the enzyme contains the conserved catalytic serine residue. In addition to the classic lipase motif GXSXG, various 1-CysPrx/aiPLA(2)s have closely related variant putative lipase motifs containing the catalytic serine residue. The PLA(2) moieties are prevalent and highly homologous in vertebrate and bacterial 1-CysPrx/aiPLA(2)s that is consistent with a high degree evolutional conservation of the enzyme.
过氧化物酶（Prx）是催化过氧化氢和烷基过氧化物还原的酶。Prx 是一种普遍存在的酶，在细菌、古菌和真核生物中都有代表。许多 1-半胱氨酸过氧化物酶（1-CysPrx）是一种具有过氧化物酶和酸性 Ca(2+)-非依赖性磷脂酶 A(2)（aiPLA(2)）双重功能的酶。1-CysPrx/aiPLA(2)的功能包括保护细胞膜磷脂免受氧化损伤（过氧化）和磷脂代谢（水解），如肺表面活性剂的磷脂。1-CysPrx 的过氧化物酶活性位点基序 PVCTTE 包含保守的催化半胱氨酸残基，而酶的酯酶（脂肪酶）基序 GXSXG 包含保守的催化丝氨酸残基。除了经典的脂肪酶基序 GXSXG 外，各种 1-CysPrx/aiPLA(2) 都具有密切相关的变体假定的脂肪酶基序，其中包含催化丝氨酸残基。在脊椎动物和细菌 1-CysPrx/aiPLA(2) 中，PLA(2) 结构域非常普遍且高度同源，这与该酶的高度进化保守性一致。
