2008年6月15日 · Methionine sulfoxide reductases (Msr) are ubiquitous enzymes, which catalyze the reduction of the sulfoxide function of the oxidized methionine residues. In vivo, the role of Msrs is described as essential in protecting cells against oxidative damages and to play a role in infection of cells by pathogenic bacteria.

氧化蛋氨酸的非对映异构体的还原是由两种不同的单体蛋氨酸亚砜还原酶（MsrA和MsrB）催化的，并且最好理解为对地球大气或可能在更局限的环境中对高水平氧气的进化响应。

2001年10月23日 · Escherichia coli and Saccharomyces cerevisiae both contain at least two Msrs. One (MsrA) is able to reduce both free and protein-bound Met (O), and the other can reduce only free Met (O). The MsrA protein is highly expressed in liver, kidney, pigment epithelial cells of the retina, macrophages, cerebellum, and brain neurons (7).

Methionine sulfoxide reductase (Msr) is a family of enzymes that reduces oxidized methionine and plays an important role in the survival of bacteria under oxidative stress conditions. MsrA and MsrB exist in a fusion protein form (MsrAB) in some pathogenic bacteria, such as Helicobacter pylori (Hp), Streptococcus pneumoniae, and Treponema denticola.

In this study, we report the first crystal structure of MsrAB from S. pneumoniae (Sp MsrAB). The Sp MsrAB consists of an N-terminal MsrA domain (Sp MsrA), a C-terminal MsrB domain (Sp MsrB) and a linker. The linker, iloop, contains conserved residues that participate in significant hydrogen bonds perhaps to maintain structural stability.

Three classes of methionine sulfoxide reductases are known: MsrA and MsrB which are implicated stereo-selectively in the repair of protein oxidized on their methionine residues; and fRMsr, discovered more recently, which binds and reduces selectively free L-Met-R-O. It is now well established that t …

2006年12月18日 · The reduction of the diastereoisomers of oxidized methionine is catalyzed by two different monomeric methionine sulfoxide reductases (MsrA and MsrB) and is best understood as an evolutionary response to high levels of oxygen either in the Earth’s atmosphere or possibly in more localized environments.

2021年3月5日 · Two different classes of Msr, named MsrA and MsrB, show distinct preferences for each diastereomer. MsrA is stereospecific for reducing L-methionine S-sulfoxide, whereas MsrB is stereospecific for the reduction of the R diastereomer [1, 5, 6, 8, 9].

2012年11月1日 · In this work, we determined the kinetic parameters of mammalian MsrA and MsrBs for the reduction of both free and peptidyl Met-O. In parallel, we also analyzed the kinetic properties of yeast MsrA and MsrB. We used yeast fRMsr to compare the free Msr activities of MsrAs and MsrBs.

Methionine sulfoxide reductase A (MsrA) is an antioxidant enzyme found in all domains of life that catalyzes the reduction of methionine-S-sulfoxide (MSO) to methionine in proteins and free amino acids. We demonstrate that archaeal MsrA has a ...