• Chemistry, Medicine
  • Published in
    Rapid communications in mass…
    2005
  • DOI:10.1002/rcm.1821

Tandem mass spectrometry of multiply phosphorylated forms of a 'histidine-tag' derived from a recombinant protein kinase expressed in bacteria.

@article{Du2005TandemMS,
  title={Tandem mass spectrometry of multiply phosphorylated forms of a 'histidine-tag' derived from a recombinant protein kinase expressed in bacteria.},
  author={Ping Du and Pat Loulakis and Zhi Xie and Samuel P. Simons and Kieran F. Geoghegan},
  journal={Rapid communications in mass spectrometry : RCM},
  year={2005},
  volume={19 4},
  pages={
          547-51
        }
}
When a histidine-tagged form of the protein kinase Aurora-2 was expressed in Escherichia coli, the purified product carried four to nine phosphate groups, although many fewer were expected. The amino-terminal tag had the sequence GSSHHHHHHSSGLVPRGSHMK-. Tryptic digestion of the product followed by analysis by liquid chromatography/mass spectrometry (LC/MS) and tandem mass spectrometry (MS/MS) showed that phosphorylation could occur on the five serine residues of the tag. Mono-, bis-, tris… CONTINUE READING