Learn More
The reactive species of oxygen and chlorine damage cellular components, potentially leading to cell death. In proteins, the sulfur-containing amino acid methionine is converted to methionine sulfoxide, which can cause a loss of biological activity. To rescue proteins with methionine sulfoxide residues, living cells express methionine sulfoxide reductases(More)
Iron/sulfur centers are key cofactors of proteins intervening in multiple conserved cellular processes, such as gene expression, DNA repair, RNA modification, central metabolism and respiration. Mechanisms allowing Fe/S centers to be assembled, and inserted into polypeptides have attracted much attention in the last decade, both in eukaryotes and(More)
Oxidation of methionine residues to methionine sulfoxide can lead to inactivation of proteins. Methionine sulfoxide reductase (MsrA) has been known for a long time, and its repairing function well characterized. Here we identify a new methionine sulfoxide reductase, which we referred to as MsrB, the gene of which is present in genomes of eubacteria,(More)
In proteins, methionine residues are primary targets for oxidation. Methionine oxidation is reversed by methionine sulfoxide reductases A and B, a class of highly conserved enzymes. Ffh protein, a component of the ubiquitous signal recognition particle, contains a methionine-rich domain, interacting with a small 4.5S RNA. In vitro analyses reported here(More)
In a previous study, we demonstrated the presence of protein aggregates in an exponentially grown Escherichia coli culture. In light of these observations, protein aggregates could be considered damage to cells that is able to pass from one generation to the next. Based on the assumption that the amount of aggregate protein could represent an aging factor,(More)
Calmodulin is known to be a target for oxidation, which leads to conversion of methionine residues to methionine sulfoxides. Previously, we reported that both methionine sulfoxide reductases MsrA and MsrB were able to reduce methionine sulfoxide residues in oxidized calmodulin. In the present study, we have made use of the interaction between calmodulin and(More)
Reactive oxygen species (ROS) are harmful because they can oxidize biological macromolecules. We show here that atmospheric CO(2) (concentration range studied: 40-1,000 p.p.m.) increases death rates due to H(2)O(2) stress in Escherichia coli in a dose-specific manner. This effect is correlated with an increase in H(2)O(2)-induced mutagenesis and, as shown(More)
Methionine ranks among the amino acids most sensitive to oxidation, which converts it to a racemic mixture of methionine-S-sulfoxide (Met-S-SO) and methionine-R-sulfoxide (Met-R-SO). The methionine sulfoxide reductases MsrA and MsrB reduce free and protein-bound MetSO, MsrA being specific for Met-S-SO and MsrB for Met-R-SO. In the present study, we report(More)
All bactericidal antibiotics were recently proposed to kill by inducing reactive oxygen species (ROS) production, causing destabilization of iron-sulfur (Fe-S) clusters and generating Fenton chemistry. We find that the ROS response is dispensable upon treatment with bactericidal antibiotics. Furthermore, we demonstrate that Fe-S clusters are required for(More)
In living organisms, most methionine residues exposed to reactive oxygen species (ROS) are converted to methionine sulfoxides. This reaction can lead to structural modifications and/or inactivation of proteins. Recent years have brought a wealth of new information on methionine sulfoxide reductase A (MsrA) and B (MsrB) which makes methionine oxidation a(More)