Related Experiment Video
Updated: Jun 20, 2026

Simultaneous Measurement of Superoxide/Hydrogen Peroxide and NADH Production by Flavin-containing Mitochondrial Dehydrogenases
Published on: February 24, 2018
A superoxide dismutase-human hemoglobin fusion protein showing enhanced antioxidative properties
Marie Grey1, Sakda Yainoy, Virapong Prachayasittikul
1Department of Pure and Applied Biochemistry, Centre for Chemistry and Chemical Engineering, Lund University, Sweden.
Abstract:
Much of the toxicity of Hb has been linked to its redox activity; Hb may generate reactive oxygen species, such as the superoxide anion. Superoxide is intrinsically toxic, and superoxide dismutase (SOD) provides important cellular protection. However, if the Hb molecule is located outside the red blood cell, the normal protection systems involving SOD and catalase are no longer closely associated with it, exposing Hb and its cellular surroundings to oxidative damage. In order to produce less toxic Hb molecules, we have explored gene fusion to obtain homogeneous SOD-Hb conjugates. The chimeric protein was generated by coexpressing the human Hb alpha-chain/manganese SOD gene together with the beta-chain gene in Escherichia coli. We show that the engineered SOD-Hb fusion protein retains the oxygen-binding capacity and, moreover, decreases cytotoxic ferrylHb (HbFe(4+)) formation when challenged with superoxide radicals. The SOD-Hb fusion protein also exhibits a 44% lower autoxidation rate and higher thermal stability than Hb alone.
Related Concept Videos
Hemoglobin
When all four heme groups are bound to oxygen, the resulting molecule is called oxyhemoglobin. As a result, arterial blood...
Gene Families
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...
Electron Transport Chain: Complex III and IV
Oxidation of Phenols to Quinones
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox property is crucial in...
Oxygen Transport in the Blood
The Supercomplexes in the Crista Membrane

