title: Characterization of recombinant human interleukin-2 with micromethods.
abstract: Highly purified recombinant human interleukin-2, expressed in Escherichia coli, was analyzed by micromethods. N-Terminal sequence analysis showed that methionine at position 0 was found in 90% of the molecules and not completely removed in post-ribosomal processing. A complete peptide map of the reduced and S-carboxymethylated protein was obtained by high-performance liquid chromatography after tryptic digestion, and the fragments were identified by amino acid analysis and automated Edman sequence analysis. Using a double-label S-carboxymethylation procedure, it was determined that there is a disulfide linkage between the cysteine residues at positions 58 and 105. The third cysteine residue at position 125 was found to be present as the free sulfhydryl.
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D004274:DNA, Recombinant; D006801:Humans; D006868:Hydrolysis; D007376:Interleukin-2 / Q000032:analysis* / Q000235:genetics; D008832:Microchemistry; D010446:Peptide Fragments / Q000032:analysis; D014357:Trypsin
chemical_list: D000596:Amino Acids; D004274:DNA, Recombinant; D007376:Interleukin-2; D010446:Peptide Fragments; D014357:Trypsin