Parasite-Host Biology Group, National Institute of Malaria Research, Indian Council of Medical Research, Sector-8, Dwarka, New Delhi, 110077, India.
Versiti Blood Center of Wisconsin, Milwaukee, WI, USA.
Parasitol Res. 2021 Feb;120(2):423-434. doi: 10.1007/s00436-021-07051-9. Epub 2021 Jan 18.
The malaria-causing parasite Plasmodium falciparum is a severe threat to human health across the globe. This parasite alone causes the highest morbidity and mortality than any other species of Plasmodium. The parasites dynamically multiply in the erythrocytes of the vertebrate hosts, a large number of reactive oxygen species that damage biological macromolecules are produced in the cell during parasite growth. To relieve this intense oxidative stress, the parasite employs an NADPH-dependent thioredoxin and glutathione system that acts as an antioxidant and maintains redox status in the parasite. The mutual interaction of both redox proteins is involved in various biological functions and the survival of the erythrocytic stage of the parasite. Since the Plasmodium species is deficient in catalase and classical glutathione peroxidase, so their redox balance relies on a complex set of five peroxiredoxins, differentially positioned in the cytosol, mitochondria, apicoplast, and nucleus with partly overlapping substrate preferences. Moreover, Plasmodium falciparum possesses a set of members belonging to the thioredoxin superfamily, such as three thioredoxins, two thioredoxin-like proteins, one dithiol, three monocysteine glutaredoxins, and one redox-active plasmoredoxin with largely redundant functions. This review paper aims to discuss and encapsulate the biological function and current knowledge of the functional redox network of Plasmodium falciparum.
疟原虫是一种严重威胁全球人类健康的寄生虫,它比其他任何疟原虫都更能引起高发病率和死亡率。这种寄生虫在脊椎动物宿主的红细胞中动态繁殖,在寄生虫生长过程中,细胞内会产生大量破坏生物大分子的活性氧。为了缓解这种强烈的氧化应激,寄生虫利用 NADPH 依赖的硫氧还蛋白和谷胱甘肽系统作为抗氧化剂,维持寄生虫的氧化还原状态。两种还原蛋白的相互作用涉及到各种生物功能和寄生虫红细胞阶段的存活。由于疟原虫缺乏过氧化氢酶和经典谷胱甘肽过氧化物酶,因此它们的氧化还原平衡依赖于一组复杂的 5 种过氧化物酶,这些酶在细胞质、线粒体、质体和核中具有不同的定位,对底物的偏好有部分重叠。此外,疟原虫还拥有一套属于硫氧还蛋白超家族的成员,如 3 种硫氧还蛋白、2 种硫氧还蛋白样蛋白、1 种二硫键、3 种单半胱氨酸谷氨酰还原酶和 1 种具有很大冗余功能的氧化还原活性的质体还原蛋白。本文旨在讨论和总结疟原虫功能性氧化还原网络的生物学功能和现有知识。