Focus on Molecules: Methionine sulfoxide reductase A

Methionine sulfoxide reductase A is a stereospecific methionine oxidase.

Methionine sulfoxide reductase A (MsrA) catalyzes the reduction of methionine sulfoxide to methionine and is specific for the S epimer of methionine sulfoxide. The enzyme participates in defense against oxidative stresses by reducing methionine sulfoxide residues in proteins back to methionine. Because oxidation of methionine residues is reversible, this covalent modification could also functio...

Selenium and the methionine sulfoxide reductase system.

Selenium is a chemical element participating in the synthesis of selenocysteine residues that play a pivotal role in the enzymatic activity efficiency of selenoproteines. The methionine sulfoxide reductase (Msr) system that reduces methionine sulfoxide (MetO) to methionine comprises the selenoprotein MsrB (MsrB1) and the non-selenoprotein MsrA, which reduce the R- and the S- forms of MetO, resp...

Methionine Sulfoxide Reductase System in Health and Disease

cell cultures has been shown to protect these cells from enhanced MetO accumulations while increasing their survival rates under oxidative stress conditions [24]. In addition, several compounds have demonstrated an ability to induce Msr activity in neuronal cell cultures [25]. This observation supports the identification and development of novel compounds that may serve as therapy treatments ag...

Complex with Protein-Bound Methionine Methionine Sulfoxide Reductase A in Mycobacterium tuberculosis

Role of Helicobacter pylori methionine sulfoxide reductase in urease maturation.

The persistence of the gastric pathogen Helicobacter pylori is due in part to urease and Msr (methionine sulfoxide reductase). Upon exposure to relatively mild (21% partial pressure of O2) oxidative stress, a Δmsr mutant showed both decreased urease specific activity in cell-free extracts and decreased nickel associated with the partially purified urease fraction as compared with the parent str...