scholarly journals Timing the Evolution of Cyanobacterial Antioxidants: Superoxide Dismutases

2021 ◽  
Author(s):  
Joanne Boden ◽  
Kurt Konhauser ◽  
Leslie Robbins ◽  
Patricia Sánchez-Baracaldo
Keyword(s):  
Superoxide Dismutase ◽  
Free Radicals ◽  
Molecular Oxygen ◽  
Chemical Change ◽  
Oxygenic Photosynthesis ◽  
Superoxide Dismutases ◽  
Copper And Zinc ◽  
Iron Nickel ◽  
Fundamental Shift ◽  
Marine Biosphere

Abstract The ancestors of cyanobacteria generated Earth’s first biogenic molecular oxygen but how they dealt with its toxicity remains unconstrained. Here we investigated when superoxide dismutase enzymes (SODs) capable of removing superoxide free radicals evolved. We found phylogenetic evidence that ancestral cyanobacteria used SODs with copper and zinc cofactors (CuZnSOD) during the Archaean. By the Paleoproterozoic, they became genetically capable of using iron, nickel, and manganese as cofactors (FeSOD, NiSOD, and MnSOD respectively). The evolution of NiSOD is particularly intriguing because it has been previously hypothesized that declining seawater Ni concentrations at the end of the Archaean caused a fundamental shift in the marine biosphere away from methanogenesis towards oxygenic photosynthesis. Our novel analyses of enzymes dealing with O2 toxicity now demonstrate that the beneficiaries of this chemical change - marine planktonic cyanobacteria - were able to utilize the remaining Ni from seawater 0.9-0.8 Ga to supplement their existing metabolic capabilities.

scholarly journals Timing the evolution of antioxidant enzymes in cyanobacteria

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Joanne S. Boden ◽  
Kurt O. Konhauser ◽  
Leslie J. Robbins ◽  
Patricia Sánchez-Baracaldo
Keyword(s):  
Oxidative Stress ◽  
Reactive Oxygen Species ◽  
Superoxide Dismutase ◽  
Antioxidant Enzymes ◽  
Free Radicals ◽  
Molecular Oxygen ◽  
Molecular Clocks ◽  
Oxygen Species ◽  
Terrestrial Habitats ◽  
Iron Nickel

AbstractThe ancestors of cyanobacteria generated Earth’s first biogenic molecular oxygen, but how they dealt with oxidative stress remains unconstrained. Here we investigate when superoxide dismutase enzymes (SODs) capable of removing superoxide free radicals evolved and estimate when Cyanobacteria originated. Our Bayesian molecular clocks, calibrated with microfossils, predict that stem Cyanobacteria arose 3300–3600 million years ago. Shortly afterwards, we find phylogenetic evidence that ancestral cyanobacteria used SODs with copper and zinc cofactors (CuZnSOD) during the Archaean. By the Paleoproterozoic, they became genetically capable of using iron, nickel, and manganese as cofactors (FeSOD, NiSOD, and MnSOD respectively). The evolution of NiSOD is particularly intriguing because it corresponds with cyanobacteria’s invasion of the open ocean. Our analyses of metalloenzymes dealing with reactive oxygen species (ROS) now demonstrate that marine geochemical records alone may not predict patterns of metal usage by phototrophs from freshwater and terrestrial habitats.

Cloning and Expression Analysis of Copper and Zinc Superoxide Dismutase (Cu/Zn-SOD) Gene fromBrassica campestrisL.

2014 ◽  
Vol 40 (4) ◽  
pp. 636 ◽  
Author(s):  
Xiu-Cun ZENG ◽  
Zi-Gang LIU ◽  
Peng-Hui SHI ◽  
Yao-Zhao XU ◽  
Jia SUN ◽  
...  
Keyword(s):  
Superoxide Dismutase ◽  
Expression Analysis ◽  
Cloning And Expression ◽  
Zinc Superoxide Dismutase ◽  
Copper And Zinc

Beneficial actions of superoxide dismutase and catalase in stunned myocardium of dogs

1986 ◽  
Vol 250 (3) ◽  
pp. H372-H377 ◽  
Author(s):  
G. J. Gross ◽  
N. E. Farber ◽  
H. F. Hardman ◽  
D. C. Warltier
Keyword(s):  
Blood Flow ◽  
Superoxide Dismutase ◽  
Free Radicals ◽  
Oxygen Free Radicals ◽  
Ischemia Reperfusion ◽  
Free Radical Scavengers ◽  
Stunned Myocardium ◽  
Regional Myocardial Blood Flow ◽  
Control Group ◽  
Myocardial Segment

Recent evidence suggests that oxygen free radicals may partially mediate irreversible ischemia-reperfusion injury in the myocardium. In the present study, the effect of a combination of two oxygen free radical scavengers, superoxide dismutase plus catalase (SOD + CAT), on the recovery of subendocardial segment function following 15 min of coronary artery occlusion followed by 3 h of reperfusion ("stunned" myocardium) was compared with a control group in barbital-anesthetized dogs. Myocardial segment shortening (%SS) in the subendocardium of nonischemic and ischemic areas was measured by sonomicrometry and regional blood flow by radioactive microspheres. SOD and CAT were infused into the left atrium 30 min before and throughout the occlusion period. Compared with the control group, %SS in the subendocardium of the ischemic region was significantly (P less than 0.05) greater in the SOD plus CAT-treated group during occlusion and throughout reperfusion. Since there were no significant differences in hemodynamics or regional myocardial blood flow between the SOD plus CAT and the control groups, these results suggest that toxic oxygen free radicals may be partially involved in the reversible ischemic injury that occurs during short periods of coronary occlusion followed by reperfusion.

Oxygen free radical-mediated selective endothelial dysfunction in isolated coronary artery

1992 ◽  
Vol 262 (3) ◽  
pp. H806-H812 ◽  
Author(s):  
K. Todoki ◽  
E. Okabe ◽  
T. Kiyose ◽  
T. Sekishita ◽  
H. Ito
Keyword(s):  
Lipid Peroxidation ◽  
Superoxide Dismutase ◽  
Free Radicals ◽  
Free Radical ◽  
Coronary Artery ◽  
Iron Chelator ◽  
Oxygen Free Radical ◽  
Alpha Tocopherol ◽  
Endothelium Dependent Relaxation ◽  
Iron Chelator Deferoxamine

To understand the direct involvement of free radicals causing reduction in endothelium-dependent relaxation of isolated canine coronary ring preparations, this study was undertaken to examine the effect of free radicals generated from dihydroxy fumarate (DHF) plus Fe(3+)-ADP or from H2O2 plus FeSO4. The vasodilators (acetylcholine, bradykinin, A23187, and nitroglycerin) were given after DHF/Fe(3+)-ADP or H2O2/FeSO4 was removed from the organ chamber. The earlier DHF/Fe(3+)-ADP exposure produced an attenuation of the relaxation of the rings induced by acetylcholine, bradykinin, or A23187 but not of the relaxation induced by nitroglycerin. The observed effect of previous DHF/Fe(3+)-ADP exposure was significantly protected in the vessels isolated from the dogs treated with alpha-tocopherol. In the experiments for assessing the effect of various scavengers, 1O2 scavenger histidine or iron chelator deferoxamine effectively protected the attenuation induced by DHF/Fe(3+)-ADP exposure of the relaxation elicited by acetylcholine; superoxide dismutase (SOD), catalase, or dimethyl sulfoxide (DMSO) had no effect on this system. Furthermore, the relaxation elicited by acetylcholine, but not nitroglycerin, was significantly attenuated by the earlier exposure to .OH generated by Fenton's reagent (H2O2+FeSO4); the attenuation was significantly protected by DMSO. These results are consistent with the view that .OH, 1O2, and/or iron-dependent reactive species selectively damage endothelium-dependent relaxation as opposed to endothelium-independent relaxation in endothelium-intact coronary ring preparations. It is also postulated that lipid peroxidation may be responsible for this effect.

Sign in / Sign up

Export Citation Format

Share Document