title: N-Glycoproteomics of Human Seminal Plasma Glycoproteins.
abstract: Seminal plasma aids sperm by inhibiting premature capacitation, helping in the intracervical transport and formation of an oviductal sperm reservoir, all of which appear to be important in the fertilization process. Epitopes such as Lewis x and y are known to be present on seminal plasma glycoproteins, which can modulate the maternal immune response. It is suggested by multiple studies that seminal plasma glycoproteins play, largely undiscovered, important roles in the process of fertilization. We have devised a strategy to analyze glycopeptides from a complex, unknown mixture of protease-digested proteins. This analysis provides identification of the glycoproteins, glycosylation sites, glycan compositions, and proposed structures from the original sample. This strategy has been applied to human seminal plasma total glycoproteins. We have elucidated glycan compositions and proposed structures for 243 glycopeptides belonging to 73 N-glycosylation sites on 50 glycoproteins. The majority of the proposed glycan structures were complex type (83%) followed by high-mannose (10%) and then hybrid (7%). Most of the glycoproteins were either sialylated, fucosylated, or both. Many Lewis x/a and y/b epitopes bearing glycans were found, suggesting immune-modulating epitopes on multiple seminal plasma glycoproteins. The study also shows that large scale N-glycosylation mapping is achievable with current techniques and the depth of the analysis is roughly proportional to the prefractionation and complexity of the sample.
authors.affiliation: Transplantation Laboratory, Haartman Institute, University of Helsinki , Haartmaninkatu 3, P.O. Box 21, Helsinki FI-00014, Finland.|HUSLAB, Helsinki University Hospital, 00290 Helsinki, Finland.
authors.forename: Mayank
authors.initials: M
authors.lastname: Saraswat
authors.affiliation: Transplantation Laboratory, Haartman Institute, University of Helsinki , Haartmaninkatu 3, P.O. Box 21, Helsinki FI-00014, Finland.|HUSLAB, Helsinki University Hospital, 00290 Helsinki, Finland.
authors.forename: Sakari
authors.initials: S
authors.lastname: Joenväärä
authors.affiliation: Department of Biophysics, All India Institute of Medical Sciences , New Delhi 110029, India.
authors.forename: Anil Kumar
authors.initials: AK
authors.lastname: Tomar
authors.affiliation: Division of Clinical Microbiology & Molecular Medicine, Department of Laboratory Medicine, All India Institute of Medical Sciences , New Delhi 110029, India.
authors.forename: Sarman
authors.initials: S
authors.lastname: Singh
authors.affiliation: Department of Biophysics, All India Institute of Medical Sciences , New Delhi 110029, India.
authors.forename: Savita
authors.initials: S
authors.lastname: Yadav
authors.affiliation: Transplantation Laboratory, Haartman Institute, University of Helsinki , Haartmaninkatu 3, P.O. Box 21, Helsinki FI-00014, Finland.|HUSLAB, Helsinki University Hospital, 00290 Helsinki, Finland.
authors.forename: Risto
authors.initials: R
authors.lastname: Renkonen
mesh_terms: D000328:Adult; D000595:Amino Acid Sequence; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D063990:Gene Ontology; D006023:Glycoproteins / Q000737:chemistry / Q000378:metabolism*; D006031:Glycosylation; D006801:Humans; D008297:Male; D011134:Polysaccharides / Q000737:chemistry / Q000378:metabolism; D020543:Proteome / Q000737:chemistry / Q000378:metabolism*; D040901:Proteomics; D012661:Semen / Q000378:metabolism*; D055815:Young Adult
chemical_list: D006023:Glycoproteins; D011134:Polysaccharides; D020543:Proteome
keywords: CID-MS/MS; DC-SIGN ligands; GlycopeptideId; HE-4; Lewis x; Lewis y; N-glycoproteomics; clusterin; heparin-affinity chromatography; human seminal plasma