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N‐ and O‐linked glycosylation site profiling of the human basic salivary proline‐rich protein 3M
Author(s) -
Manconi Barbara,
Cabras Tiziana,
Sanna Monica,
Piras Valentina,
Liori Barbara,
Pisano Elisabetta,
Iavarone Federica,
Vincenzoni Federica,
Cordaro Massimo,
Faa Gavino,
Castagnola Massimo,
Messana Irene
Publication year - 2016
Publication title -
journal of separation science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.72
H-Index - 102
eISSN - 1615-9314
pISSN - 1615-9306
DOI - 10.1002/jssc.201501306
Subject(s) - chemistry , asparagine , tandem mass spectrometry , glycosylation , electrospray ionization , glycan , threonine , peptide , mass spectrometry , chromatography , biochemistry , isobaric labeling , saliva , deamidation , protein mass spectrometry , amino acid , enzyme , glycoprotein , serine
In the present study, we show that the heterogeneous mixture of glycoforms of the basic salivary proline‐rich protein 3M, encoded by PRB3‐M locus, is a major component of the acidic soluble fraction of human whole saliva in the first years of life. Reversed‐phase high‐performance liquid chromatography with high‐resolution electrospray ionization mass spectrometry analysis of the intact proteoforms before and after N‐deglycosylation with Peptide‐N‐Glycosidase F and tandem mass spectrometry sequencing of peptides obtained after Endoproteinase GluC digestion allowed the structural characterization of the peptide backbone and identification of N‐ and O‐glycosylation sites. The heterogeneous mixture of the proteoforms derives from the combination of 8 different neutral and sialylated glycans O‐linked to Threonine 50, and 33 different glycans N‐linked to Asparagine residues at positions 66, 87, 108, 129, 150, 171, 192, and 213.