Analysis of isoaspartate in peptides and proteins without the use of radioisotopes.

@article{Schurter2000AnalysisOI,
  title={Analysis of isoaspartate in peptides and proteins without the use of radioisotopes.},
  author={B T Schurter and Dana W Aswad},
  journal={Analytical biochemistry},
  year={2000},
  volume={282 2},
  pages={227-31}
}
A rapid and sensitive HPLC-based method for quantitating isoaspartate levels in peptides and proteins is described. The analyte is incubated for 40 min with S-adenosyl-l-methionine and the commercially available enzyme protein l-isoaspartyl methyltransferase. Methylation of isoaspartyl sites results in stoichiometric production of S-adenosyl-l-homocysteine that is separated from the other components of the reaction by reversed-phase HPLC and quantitated online by absorbance at 260 nm. This… CONTINUE READING