Lectin-Binding Specificity of the Fertilization-Relevant Protein PDC-109 by Means of Surface Plasmon Resonance and Carbohydrate REcognition Domain EXcision-Mass Spectrometry

Abstract

Seminal plasma proteins are relevant for sperm functionality and some appear responsible for establishing sperm interactions with the various environments along the female genital tract towards the oocyte. In recent years, research has focused on characterizing the role of these proteins in the context of reproductive biology, fertility diagnostics and treatment of related problems. Herein, we focus on the main protein of bovine seminal plasma, PDC-109 (BSP-A1/-A2), which by virtue of its lectin properties is involved in fertilization. By means of surface plasmon resonance, the interaction of PDC-109 with a panel of the most relevant glycosidic epitopes of mammals has been qualitatively and quantitatively characterized, and a higher affinity for carbohydrates containing fucose has been observed, in line with previous studies. Additionally, using the orthogonal technique of Carbohydrate REcognition Domain EXcision-Mass Spectrometry (CREDEX-MS), the recognition domain of the interaction complexes between PDC-109 and all fucosylated disaccharides [(Fuc-α1,(3,4,6)-GlcNAc)] has been defined, revealing the specific glycotope and the peptide domain likely to act as the PDC-109 carbohydrate binding site.

Two-dimensional isomer differentiation using liquid chromatography-tandem mass spectrometry with in-source, droplet-based derivatization

“…Carbohydrates are a structurally complex class of molecules that serve diverse biological functions from building and maintaining energy stores to cellular signalling, immune response, and gene regulation. [1][2][3][4][5][6][7] Physiological responses differ depending on the nature of the constituent monomers, the configuration of stereocenters and anomeric sites, and connectivity at the glycosidic linkage, [8][9][10] the varying combinations of which govern bioavailability and metabolism. For example, sucrose and palatinose are both disaccharides comprised of one glucose and one fructose monomer that differ only in the connectivity of the glycosidic bond.…”

Identification and Affinity Determination of Protein-Antibody and Protein-Aptamer Epitopes by Biosensor-Mass Spectrometry Combination

“…The molecular characterization of antibody epitopes of a peptide or protein antigen is a key element for the discovery of biomarkers, vaccines and in drug development [ 4 , 6 , 7 , 10 , 11 , 12 ]. It is well established that antibodies bind to different peptide or protein ligands via linear (sequence) or assembled (“conformational”) epitopes [ 4 ].…”