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Human alpha-fetoprotein primary structure: a mass spectrometric study.

P Pucci·R Siciliano·A Malorni·G Marino·M F Tecce·C Ceccarini·B Terrana
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Abstract

The amino acid sequence of human alpha-fetoprotein, a 67-kDa protein present in mammalian embryonic serum, was verified by fast atom bombardment mass spectrometric (FAB/MS) analyses of three different enzymatic digests of the protein. Human alpha-fetoprotein obtained from a large-scale cell culture was digested with trypsin and V-8 protease either separately on two different samples or combined on the same one. The V-8 protease digest of the protein was partially fractionated by HPLC; the other samples were directly analyzed by FAB/MS without previous purification steps. About 90% of the alpha-fetoprotein amino acid sequence was verified by mass spectrometric analysis; this also confirmed that the cell-derived protein is identical with the hepatoma-derived protein. FAB analysis revealed that the N terminus of the mature protein is arginine rather than threonine, with the threonine occupying the second position. Therefore, the processing site of the alpha-fetoprotein signal peptide during maturation of the protein occurs at the N-terminal side of the arginine residue formerly indicated as residue-1. Thus mature alpha-fetoprotein contains 591 amino acids rather than 590.

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Amino Acid SequenceAnimalsCell LineChromatography, High Pressure LiquidHumansMiceMolecular Sequence DataPeptide FragmentsRatsSequence Homology, Nucleic AcidSpectrometry, Mass, Fast Atom Bombardmentalpha-FetoproteinsComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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P Pucci, R Siciliano, A Malorni, G Marino, M F Tecce, C Ceccarini, B Terrana. 1991-05-21. Human alpha-fetoprotein primary structure: a mass spectrometric study.. https://doi.org/10.1021/bi00234a032

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