Sites of phosphorylation in recombinant human interferon-gamma.
Recombinant human interferon-gamma was phosphorylated with ATP and c-AMP-dependent protein kinase. After phosphorylation, interferon-gamma was separated from the adenosine phosphates and the kinase and analyzed by SDS-PAGE, reverse phase HPLC, and HPLC peptide mapping. Comparison of the S. aureus V8 protease maps of intact and phosphorylated interferon-gamma showed that the maps were identical except that one peptide fragment elutes earlier in the map of the phosphorylated sample. This peptide was identified as the C-terminal fragment containing two serinyl phosphorylation sites at positions 132 and 142. This phosphorylated interferon-gamma exhibited a slightly higher specific antiviral activity than the intact protein.
D000255:Adenosine Triphosphate / Q000378:metabolism; D000595:Amino Acid Sequence; D002851:Chromatography, High Pressure Liquid; D000242:Cyclic AMP / Q000494:pharmacology; D003588:Cytopathogenic Effect, Viral; D010450:Endopeptidases; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism* / Q000494:pharmacology; D010446:Peptide Fragments; D010750:Phosphoproteins / Q000378:metabolism*; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism*; D012697:Serine Endopeptidases
D010446:Peptide Fragments; D010750:Phosphoproteins; D011994:Recombinant Proteins; D007371:Interferon-gamma; D000255:Adenosine Triphosphate; D000242:Cyclic AMP; D011494:Protein Kinases; D010450:Endopeptidases; D012697:Serine Endopeptidases; C028344:glutamyl endopeptidase