Plasma desorption mapping of the tryptic digest of 23-kDa recombinant human growth hormone.
Plasma desorption mass spectrometry has been used to map the tryptic fragments from the 23-kDa recombinant human growth hormone protein. The unfractionated tryptic digest was adsorbed directly onto a nitrocellulose sample foil and mass spectra were obtained in both the positive and the negative ion mode. The adsorbed sample was then washed with deionized water and its mass spectrum was again obtained. The latter spectrum revealed tryptic fragments that were not observed in the spectra of the unwashed sample, which can be attributed (to some extent) to the removal of hydrophilic residues during washing. From this study a protocol, aimed at the complete mapping of tryptic fragments, is outlined.
Chen
L
L
Department of Pharmacology and Molecular Sciences, Johns Hopkins University, School of Medicine, Baltimore, Maryland 21205.
Cotter
R J
RJ
Stults
J T
JT
D000595:Amino Acid Sequence; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D013006:Growth Hormone / Q000032:analysis*; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods; D008969:Molecular Sequence Data; D010449:Peptide Mapping; D011994:Recombinant Proteins / Q000032:analysis*; D014357:Trypsin / Q000378:metabolism
D011994:Recombinant Proteins; D013006:Growth Hormone; D014357:Trypsin