Sources of S-adenosyl-L-homocysteine background in measuring protein arginine N-methyltransferase activity using tandem mass spectrometry

作者：Lakowski Ted M; Frankel Adam^*

来源：Analytical Biochemistry, 2010, 396(1): 158-160.

DOI：10.1016/j.ab.2009.08.043

S-Adenosyl-L-homocysteine (AdoHcy) background signal in reactions with protein arginine N-methyltransferase I is investigated using an ultrahigh-performance liquid chromatography tandem mass spectrometry assay that measures AdoHcy. We identify three sources of AdoHcy background: enzymatic automethylation, AdoHcy contamination in commercial S-adenosyl-L-methionine (AdoMet), and nonenzymatic pseudo-first-order formation of AdoHcy from AdoMet. We propose a potential mechanism for the nonenzymatic production of AdoHcy and illustrate strategies for mitigating background AdoHcy that can be applied to any assay.

• 出版日期2010-1-1