MsrB2 Protein 6xHis

6xHis MsrB2 Protein aa: 42-182 (2 x 50 micrograms)

The Msr family are well conserved proteins that function to reduce oxidized methionine to L-methionine. The SelR (MsrB) protein was identified as the enzyme responsible for reduction of the MICAL-oxidized Met 44 and Met47 amino acids of actin.. As part of the MOXtrue™ product line,human MSRB2 protein (MB201) [accession # Q9Y3D2 (MSRB2_HUMAN)] has been produced and purified from a bacterial expression system. The recombinant protein is N-terminally 6x Histidine tagged and is comprised of amino acids 42-182. Validation studies have shown that MB201 can reduce MICAL-oxidized actin which will enhance subtilisin A cleavage by >90% in limited proteolysis assays.  MB201 has also been validated for the production of reduced actin which can be used in downstream applications such as sedimentation assays and actin polymerization assays. 

To learn more about using MsrB2 as a research tool see our datasheet 

To learn more about the MICAL/MsrB/Actin physiological redox system see our Newsletter 

Each lot of purified protein is quality controlled  to provide high batch to batch consistency, see COA documents.

Subtilisin Assay on MsrB2 Treated Oxidized Actin

MICAL-oxidized actin (MetO Actin) (Cat# MXA95) was diluted to 0.1 mg/ml (2.3 μM) and left untreated, or treated with DTT (10 mM), MB201 (0.3 μM) , or a combination of both (see method). 2 mg of each sample was then left untreated, or treated with subtilisin (1:200 w/w) for 15 min.  Samples were then separated by SDS-PAGE and visualized with Coomassie staining. 

Click here for a detailed method 


Oxidized Actin Polymerization +/- MsrB2 Treatment

Pyrene-labeled actin (Cat # AP05) and MICAL-oxidized pyrene labeled actin (Cat. # MPAX1) were diluted to 0.1 mg/ml (2.3 μM) (see method). Samples were then incubated with 2x polymerization buffer supplemented with nothing (labeled Control), DTT alone (labeled +DTT), MB201 0.3 µM + DTT (labeled +MB201 0.3), or MB201 1.2 µM + DTT (labeled +MB201 1.2),.  Upon actin polymerization fluorescence was detected with a spectrophotometer (see method below). A.U. = arbitrary units

Click here for a detailed method 


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Associated Products:

MOXtrue™ 6xHis MICAL-1 Protein (Cat. # MIC01)

MOXtrue™ MICAL-oxidized Actin (Cat. # MXA95)

MOXtrue™ MICAL-oxidized Pyrene Labeled Actin (Cat. # MPAX1)

Rabbit Skeletal Muscle Actin (Cat. # AKL95)

Pyrene Labeled Rabbit Skeletal Muscle Actin (Cat.# AP05)

For product Datasheets and MSDSs please click on the PDF links below.

Certificate of Analysis:  Lot 015

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