Superoxide Dismutases in Eukaryotic Microorganisms: Four Case Studies

Abstract

Various components in the cell are responsible for maintaining physiological levels of reactive oxygen species (ROS). Several different enzymes exist that can convert or degrade ROS; among them are the superoxide dismutases (SODs). If left unchecked, ROS can cause damage that leads to pathology, can contribute to aging, and may, ultimately, cause death. SODs are responsible for converting superoxide anions to hydrogen peroxide by dismutation. Here we review the role of different SODs on the development and pathogenicity of various eukaryotic microorganisms relevant to human health. These include the fungal aging model, Podospora anserina; various members of the genus Aspergillus that can potentially cause aspergillosis; the agents of diseases such as Chagas and sleeping disease, Trypanosoma cruzi and Trypanosoma brucei, respectively; and, finally, pathogenic amoebae, such as Acanthamoeba spp. In these organisms, SODs fulfill essential and often regulatory functions that come into play during processes such as the development, host infection, propagation, and control of gene expression. We explore the contribution of SODs and their related factors in these microorganisms, which have an established role in health and disease.

Sanitizing of stainless steel surfaces in the food industry: Effect of gaseous ozone against pathogens and filamentous fungi

“…Its resistance to some physical sanitizing agent such as the UVC (and UVC‐LED) light had been already assessed (Belloli et al, 2022; Racchi et al, 2021) and attributed to the great amounts of melanin and melanin‐like pigments in its outer cellular wall (Krijgsheld et al, 2013; Pombeiro‐Sponchiado et al, 2017). Furthermore, it must be taken into account that, like other filamentous fungi in the genus Aspergillus , it possesses good amounts of ROS‐scavenging enzymes such as the superoxide dismutases (SOD) and the catalases (CAT) (Valle et al, 2022). SOD proved critical to cell survival following ozone exposure by eliminating the superoxide radicals, and thereby preventing the formation of hydroxyl radicals, whereas CAT proved necessary for protection against ozone exposure (Fisher et al, 2000).…”

Coumarin-based derivatives targetingTrypanosoma cruzicruzain andTrypanosoma bruceicathepsin L-like proteases

“…Then, when a methyl group is inserted at position 7 of MP-05 , a compound (MP-04) , with similar activity against T. cruzi CRZ (NI: 35% ± 2 and I: 31% ± 1) and Tbr CATL (NI: 15% ± 1 and I: 7% ± 1) was obtained. Since nitro-containing derivatives are associated with antiparasitic activity against T. cruzi 47 and T. b. brucei , 48 as these compounds can inhibit the iron superoxide dismutase (Fe-SOD) enzyme – which plays a fundamental role in protecting the parasite against oxidative damage due to the generation of ROS on epimastigotes and amastigotes, 49–52 a 6-nitro-containing coumarin (MP-03) was investigated against both targets, demonstrating poor inhibition before (CRZ NI: 21% ± 1 and Tbr CATL NI: 10% ± 1) and after (CRZ I: 10% ± 1 and Tbr CATL I: 1% ± 2) pre-incubation. Posteriorly, when a methyl group was replaced with a methoxyl group, a coumarin (FN-07) with similar CRZ inhibition activity was obtained, although it presented some improvement in the Tbr CATL inhibition activity (NI: 17% ± 1 and I: 12% ± 1).…”

Global Transcriptomic Changes Elicited by sodB Deletion and Menadione Exposure in Aspergillus nidulans

“…Fungal MnSODs play a complex role in oxidative stress defense via maintaining the integrity and functions of mitochondria under both endogenous and exogenous superoxide stresses [2][3][4][5]. Not surprisingly, MnSODs have been reported as key elements in the regulation of versatile physiological processes responding to changing intracellular reac- S3.…”

“…•− ) into molecular oxygen (O 2 ) and hydrogen peroxide (H 2 O 2 ) and, hence, they are basic elements of oxidative stress defense [1,2]). Manganese-SODs (MnSODs) are primarily localized in the mitochondria of yeasts and filamentous fungi and are key players in the maintenance of mitochondrial integrity and functions [2][3][4][5].…”