Vigneswara, V., Lowenson, J.D., Powell, C.D., Thakur, M., Bailey, K., Clarke, S., Ray, D.E. and Carter, W.G.
Notes: The authors used the ISOQUANT Isoaspartate Detection Kit to methylate isoaspartyl residues of proteins in mouse brain tissue extracts. The use of the radiolabeled methyl donor S-adenosyl-[3H-methyl]methionine allowed the quantitation of methylation and the identification of L-isoaspartate O-methyltransferase substrates using one dimensional and two-dimensional electrophoresis. Extracts were methylated with recombinant bovine protein isoaspartyl methyltransferase using 20µM S-adenosyl-[3H-methyl]methionine in 100 mM sodium phosphate, pH 6.8, containing 1mM EGTA, 0.16% Triton® X-100, and 0.004% sodium azide for 30 minutes at 30°C. (3559)