Hydrogen Sulfide Induces Oxidative Damage to RNA and DNA in a Sulfide‐Tolerant Marine Invertebrate

Abstract

Hydrogen sulfide acts as an environmental toxin across a range of concentrations and as a cellular signaling molecule at very low concentrations. Despite its toxicity, many animals, including the mudflat polychaete Glycera dibranchiata, are periodically or continuously exposed to sulfide in their environment. We tested the hypothesis that a broad range of ecologically relevant sulfide concentrations induces oxidative stress and oxidative damage to RNA and DNA in G. dibranchiata. Coelomocytes exposed in vitro to sulfide (0–3 mmol L−1 for 1 h) showed dose-dependent increases in oxidative stress (as 2′,7′-dichlorofluorescein fluorescence) and superoxide production (as dihydroethidine fluorescence). Coelomocytes exposed in vitro to sulfide (up to 0.73 mmol L−1 for 2 h) also acquired increased oxidative damage to RNA (detected as 8-oxo-7,8-dihydroguanosine) and DNA (detected as 8-oxo-7,8-dihydro-2′-deoxyguanosine). Worms exposed in vivo to sulfide (0–10 mmol L−1 for 24 h) acquired elevated oxidative damage to RNA and DNA in both coelomocytes and body wall tissue. While the consequences of RNA and DNA oxidative damage are poorly understood, oxidatively damaged deoxyguanosine bases preferentially bind thymine, causing G-T transversions and potentially causing heritable point mutations. This suggests that sulfide can be an environmental mutagen in sulfide-tolerant invertebrates.

Effects of stocking density on the growth performance, physiological response and intestinal microbiota of juvenile Echiura worms ( Urechis unicinctus )

“…Death of U. unicinctus juveniles in the 200 U group might be due to the presence of sulphides in the sediments. Excessive sulphides in the sediments are toxic to cultured organisms and can lead to apoptosis and oxidative damage (Joyner‐Matos, Predmore, Stein, Leeuvenburgh & Julian, 2010; Yang, Sun, & Wang, 2004). Although U. unicinctus is more resistant to sulphides than other benthic invertebrates (Zhang & Li 2011), the 200 U group was exposed to extremely high sulphide levels when compared to other stocking densities (Table 1).…”

Generation of DNA-Damaging Reactive Oxygen Species via the Autoxidation of Hydrogen Sulfide under Physiologically Relevant Conditions: Chemistry Relevant to Both the Genotoxic and Cell Signaling Properties of H2S

“…In a separate study, H 2 S was found to cause increased levels of 8-oxo-7,8-dihydro-2′-deoxyguanosine in coelomocytes and in Glycera dibranchiata . 35 In cultured human lung fibroblasts, H 2 S induced a concentration-dependent increase in micronuclei, a finding suggestive of DNA damage. 36 Finally, H 2 S was shown to be weakly mutagenic in the Salmonella typhimurium strain 1535.…”

Synechococcus sp. Strain PCC7002 Uses Sulfide:Quinone Oxidoreductase To Detoxify Exogenous Sulfide and To Convert Endogenous Sulfide to Cellular Sulfane Sulfur

“…The toxic effect of sulfide is well known, inhibiting respiration by acting on cytochrome c oxidase in heterotrophic bacteria (12)(13)(14)(15) and photosynthesis by binding to metalloproteins of photosynthesis system II (PSII) (16)(17)(18)(19). Sulfide can reach high concentrations in specific habitats, such as hydrothermal vents and seeps (10) and coastal mudflats (11). Sulfide is mainly derived from sulfate as the terminal electron acceptor for organic mineralization by sulfur-reducing bacteria in OMZs (10).…”