The multiplicity of N-glycan structures of bovine milk 18 kda lactophorin (milk GlyCAM-1).
Lactophorin is a heat-stable phosphoglycoprotein, also known as milk glycosylation-dependent cell adhesion molecule 1 (GlyCAM-1). Bovine 18 kDa lactophorin was purified by heparin affinity chromatography from cow's milk whey. Its N-glycans were obtained by proteomic techniques, including two-dimensional polyacrylamide gel electrophoresis (2D-PAGE), followed by in-gel digestion with peptide-N(4)-(N-acetyl-beta-glucosaminyl)-asparagine amidase (PNGase F). The released N-glycans were derivatized with 2-aminopryridine (PA) and analyzed by matrix-assisted laser desorption ionization quadruple ion trap time of flight mass spectrometry (MALDI-QIT-TOF MS). Among the MS analyzed peaks, 15 peaks were found to be N-glycan molecules as detected by MS(2) analysis. These glycans consisted of mono-sialylated bi-, tri-, and tetra-antennary complex-type N-glycans carrying Gal-GlcNAc (LacNAc) or GalNAc-GlcNAc (LacdiNAc) with and without core-fucose.
United Graduate School of Agricultural Science, Gifu University, Japan.
Mizuho
M
Inagaki
Shuuichi
S
Nakaya
Daisuke
D
Nohara
Tomio
T
Yabe
Yoshihiro
Y
Kanamaru
Tohru
T
Suzuki
D000818:Animals; D002417:Cattle; D005260:Female; D008894:Milk Proteins / Q000737:chemistry*; D008970:Molecular Weight; D009077:Mucins / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry*
D008894:Milk Proteins; D009077:Mucins; D011134:Polysaccharides; C061124:lactophorin protein, Bos taurus; C075185:sulfated glycoprotein p50