Hemoglobin and cytochrome c. reinterpreting the origins of
2023年9月7日 · We determined the redox status of the iron ion in whole blood (without and with anticoagulant), hemoglobin in erythrocytes, in isolated cytochrome c and cytochrome c in mitochondria of the...
Redox Reactions of Hemoglobin: Mechanisms of Toxicity and …
Hemin iron atoms within Hb undergo spontaneous oxidation from ferrous to ferric oxidation states. This process indirectly produces hydrogen peroxide, which can further react with ferric and ferrous Hb to produce ferryl species. Reductases within red blood cells keep the heme iron in …
Oxidation of hemoglobin: mechanisms of control in vitro and …
2008年6月28日 · In the present review we discuss mechanisms of Hb and HBOC autoxidation, nitrosylation and peroxidation in vitro and in vivo. Additionally, we explore the role (s) of plasma antioxidants in maintaining functional HBOC status that may potentially be exploited as part of protective strategies against Hb and HBOC oxidative toxicity.
Oxidative instability of hemoglobin E (β26 Glu→Lys) is increased …
2016年3月10日 · We have found that although both HbA and HbE autoxidize at initially comparable rates, HbE loses heme at a rate almost 2 fold higher than HbA due to unfolding of the protein. Using mass spectrometry and the spin trap, DMPO, we were able to quantify irreversible oxidization of βCys93 to reflect oxidative instability of β subunits.
Molecular Mechanisms of Iron and Heme Metabolism - PMC
While most of the body’s iron complement is found in heme, iron can also be incorporated into iron-sulfur clusters or bind directly to proteins. In addition to its role in oxygen transport as a component of hemoglobin, iron is critical for multiple biological pathways including DNA metabolism and mitochondrial function.
Differential heme release from various hemoglobin redox states …
Hemoglobin undergoes spontaneous oxidation from the ferrous (Fe 2+) to the ferric (Fe 3+) states in the presence of air equilibrated aqueous buffer and produces superoxide anions (O 2 ·¯) 2. The released O 2 ·¯ then undergoes dismutation to H 2 O 2 and O 2, and the H 2 O 2 produced in this step can react with the protein to produce several ...
In this article, we review two important redox reactions of hemoglobin and discuss the ramifications of these reactions. The reduction of oxygen to superoxide starts a cascade of oxidative reactions, which are a source for red cell-induced oxidative stress.
βCysteine 93 in human hemoglobin: a gateway to oxidative
2020年9月26日 · βcysteine 93 residue plays a key role in oxygen (O 2)-linked conformational changes in the hemoglobin (Hb) molecule. This solvent accessible residue is also a target for...
The pathophysiology of extracellular hemoglobin associated with ...
2015年1月13日 · Hemoglobin (Hb) continuously undergoes autoxidation producing superoxide which dismutates into hydrogen peroxide (H 2 O 2) and is a potential source for subsequent oxidative reactions. Autoxidation is most pronounced under hypoxic conditions in the microcirculation and for unstable dimers formed at reduced Hb concentrations.
Hemoglobin: Multiple molecular interactions and multiple …
2022年4月1日 · When the ferrous iron of the heme (Fe 2+) is oxidized to Fe 3+, the hemoglobin function is greatly modified giving rise to an increase of oxygen affinity and a decrease of cooperativity. At the end, this may result in the complete loss of the ability of exchanging the oxygen molecule ( Antonini E. et al., 1965 ; Perrella M. et al., 1993 ).