Products

SAM510^TM, SAM Methyltransferase assay

Methylation of key biological molecules and proteins plays important roles in numerous biological systems,

including signal transduction, biosynthesis, protein repair, gene silencing and chromatin regulation. 

The S-adenosylmethionine (SAM) dependent methyltransferases use SAM, the second most commonly

used enzymatic cofactor after ATP.  SAM, also known as AdoMet, acts as a donor of a methyl group that is

required for the modification of proteins and DNA.  Aberrant levels of SAM have been linked to many

abnormalities, including Alzheimer’s, depression, Parkinson’s, multiple sclerosis, liver failure and cancer.

The SAM510™: SAM Methyltransferase Assay is a continuous enzyme coupled assay that can continuously

monitor purified SAM-dependent methyltransferases without the use of radioactive labels or endpoint

measurements.

Figure in below outlines the general scheme of the assay. Basically, the removal of the methyl group from

SAM generates S-adenosylhomocysteine, which is rapidly converted to S-ribosylhomocysteine and adenine

by the included adenosylhomocysteine nucleosidase. This rapid conversion prevents the buildup of

adenosylhomocysteine and its feedback inhibition on the methylation reaction. Finally, the adenine is

converted to hypoxanthine, by adenine deaminase, which in turn is converted to urate and hydrogen

peroxide. The rate of production of hydrogen peroxide is measured with a colorimetric assay by an increase

in absorbance at 510nm.

The assay can be adapted to be used with any purified SAM dependent methyltransferase or a purified

enzyme that produces 5-adenosylhomocysteine or 5'-methylthioadenosine, due to the specificity of

adenosylhomocysteine nucleosidase.

The kit is supplied with enough reagents for 100 x 115µl microwell assays.

A UV SAM methyltransferase assay and a fluorescent SAM methyltransferase assay are also available.

Features

• Kinetic analysis of purified methyltransferases or screening methylation inhibitors.

• Continuous enzyme coupled assay for kinetic studies.

• Colorimetric, non radioactive assay.

• Supplied with all reagents, including positive control.

• Adaptable for enzymes that generate S-adenosylhomocysteine or 5'-methylthioadenosine.

Applications

• For the kinetic analysis of protein SAM methyltransferase enzymes.

• Ideal for screening of methyltransferase inhibitors.

References

• Horiuchi, K.Y. (2015) Drug Discov Today Technol. 18:62

• Chatterjee, T. et al. (2015) Arch Biochem Biophys doi:10.1016/j.abb.2015.08.001

• Richard-Greenblatt, M. et al (2015) J Biol Chem. doi: 10.1074/jbc.M115.648642

• Shaiwale, N.S. et al (2015) J. Proteome. 126:131

• Sharma, S. et al (2013) Nucleic Acids Res. 42:3246

• Kumar, A. et al (2011) J Biol Chem 286:19652

• Carney, A. and Holden, H.M. (2011) Biochemistry. 50:780

• Pei, H. et al (2011) Nature. 470:124

Instruction sheet (PDF)

Catalog No.

Product Name

Size

786-430

               SAM510™, SAM methyltransferase Assay

100 assays