Variations and Distributions of O-Glycosidically Linked Sugar Chains in Bovine κ-Casein

Saito, Tadao; Itoh, Takatoshi

doi:10.3168/jds.s0022-0302(92)77936-3

Cited by 133 publications

(101 citation statements)

References 14 publications

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“…For phosphoproteins, such a mass difference is typical of phosphorylation (Feng et al, 1991). K-CN is known to exhibit microheterogeneity because of O-glycosylation (Van Halbeek et al, 1980;Vreeman et al, 1986;Saito and Itoh, 1992). These glycosylated forms are distributed over several molecular species that elute just before the major chromatographic peak (Léonil and Mollé, 1991), however, none of them were detected under our LC/ESI-MS conditions.…”

Section: K-cnmentioning

confidence: 75%

Analysis of major bovine milk proteins by on-line high-performance liquid chromatography and electrospray ionization-mass spectrometry

Léonil

Mollé²,

Gaucheron³

et al. 1995

Lait

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Summary -Proteins from skim milk, paracaseinate and whey have been successfully analyzed by reverse-phase high-pertormance liquid chromatography (RP-HPLC) cou pied with electrospray ionization mass spectrometry (ESI-MS). The major milk proteins were identified by comparison of molecular masses determined by ESI-MS to molecular masses calculated from amino acid composition deduced from primary structures and cDNA sequences for some proteins. This method has permilted the simultaneous identification of caseins and whey protein variants. Observed molecular masses of major milk proteins were found to be 19038.0 ± 2.2 Da forK-CN A-l P (number of experiments n = 6); 19007.0 ± 1.1 Da for K-CN B-1P (n = 4); 25230.0 ± 2.1 Da for as2-CN A (n = 9); 23617.2 ± 1.3 Da for as1-CN B-8P (n = 14); 24 092.0 ± 1.7 Da for~-CN B-5P (n = 6); 24 025.3 ± 1.0 Da for~-CN A 1-5P (n = 14); 23 984.8 ± 0.7 Da for~-CN A2_5P (n = 14); 18278.3 ± 2.2 Da for the monomeric form of~-LG B (n = 5); 18 364.8 ± 1.6 Da for the monomeric form of~-LG A (n = 5); 14 179.21 ± 3.14 Da for a-LA (n = 5). Hence an accuracy of 0.01 % was obtained by ESI-MS analysis. It was also shown that the on-line coupling of HPLC with ESI-MS offers a very promising alternative for studying the proteolysis and determining the specificity of used enzymes in some technological treatments as shown for milk-clotting enzymes.

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Section: K-cnmentioning

confidence: 75%

Analysis of major bovine milk proteins by on-line high-performance liquid chromatography and electrospray ionization-mass spectrometry

Léonil

Mollé²,

Gaucheron³

et al. 1995

Lait

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“…CMP is heterogeneous and contains all the posttranslational modification sites (glycosylation and phosphorylation) of -casein. Six potential glycosylation sites have been identified on CMP (18), and up to five different carbohydrate moieties may be attached at each site (20). Three genetic variants of CMP have also been identified, originating from the precursors -casein A, B, and E, with variants A and B being the most common in bovine milk (15).…”

mentioning

confidence: 99%

Kappacin, a Novel Antibacterial Peptide from Bovine Milk

Malkoski

Dashper

O'Brien-Simpson

et al. 2001

Antimicrob Agents Chemother

187

141

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Caseinomacropeptide (CMP) is a heterogeneous C-terminal fragment (residues 106 to 169) of bovine milk -casein composed of glycosylated and phosphorylated forms of different genetic variants. We have demonstrated that CMP has growth-inhibitory activity against the oral opportunistic pathogens Streptococcus mutans and Porphyromonas gingivalis and against Escherichia coli. CMP was fractionated using reversed-phase highperformance liquid chromatography (RP-HPLC), and each fraction was tested for activity against S. mutans in a 96-well-plate broth assay. Fractions were characterized by N-terminal sequence analysis and mass spectrometry. The active form of CMP was shown to be the nonglycosylated, phosphorylated -casein (residues 106 to 169) [-casein(106-169)], which we have designated kappacin. Endoproteinase Glu-C was used to hydrolyze CMP, and the generated peptides were separated using RP-HPLC and gel filtration-HPLC and then tested for activity against S. mutans. The peptide Ser(P) 149 -casein-A(138-158) was the only peptide generated by endoproteinase Glu-C digestion that exhibited growth-inhibitory activity. Peptides corresponding to the sequences of the inhibitory peptide Ser(P) 149 -casein-A(138-158) and its nonphosphorylated counterpartcasein-A(138-158) were chemically synthesized and tested for antibacterial activity. The synthetic Ser(P) 149-casein-A(138-158) displayed growth-inhibitory activity against S. mutans (MIC, 59 g/ml [26 M]). The nonphosphorylated peptide, however, did not inhibit growth at the concentrations tested, indicating that phosphorylation is essential for activity.The caseins are the most abundant bovine milk proteins, and there are four major types: ␣ s1 -, ␣ s2 -, ␤-, and -casein (23). All four caseins are phosphorylated on specific seryl residues, and in addition, -casein is glycosylated (4). -Casein is hydrolyzed by the enzyme chymosin between Phe 105 and Met 106 , generating two polypeptides: a hydrophobic N-terminal para--casein polypeptide -casein (residues 1 to 105) [-casein(1-105)] and a hydrophilic phosphorylated and glycosylated C-terminal polypeptide -casein(106-169), known as the caseinomacropeptide (CMP). CMP is heterogeneous and contains all the posttranslational modification sites (glycosylation and phosphorylation) of -casein. Six potential glycosylation sites have been identified on CMP (18), and up to five different carbohydrate moieties may be attached at each site (20). Three genetic variants of CMP have also been identified, originating from the precursors -casein A, B, and E, with variants A and B being the most common in bovine milk (15).CMP and CMP-derived peptides have been reported to have a variety of biological activities, such as suppression of gastric secretions (28), depression of platelet aggregation (2), inhibition of influenza virus hemagglutination (8), inhibition of cholera toxin binding (9), and immunomodulating activities (14). CMP has also been shown to incorporate into salivary pellicle and inhibit the adherence of Streptococcus mutans, the oral...

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“…Many researchers [Tran & Baker, 1970;Fiat et al, 1972;Jolles et al, 1972;Fournet et al, 1975;Doi et al, 1979;Van Halbeek et al, 1980;Saito et al,1981;Saito & Itoh, 1992] contributed to information about the saccharide structures in GMP. In mature cow's milk it has been established that fi ve saccharides are found: GalNAc -O -R where, Gal: galactose; GalNAc: N-acetylgalactosamine, and NeuAc: sialic acid.…”

Section: Structure Of Glycomacropeptidementioning

confidence: 99%

Healthy Multifunctional Spectra of Milk Glycoproteins and Their Fragments – a Review Article

Fayed¹

2012

Pol. J. Food Nutr. Sci.

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Variations and Distributions of O-Glycosidically Linked Sugar Chains in Bovine κ-Casein

Cited by 133 publications

References 14 publications

Analysis of major bovine milk proteins by on-line high-performance liquid chromatography and electrospray ionization-mass spectrometry

Analysis of major bovine milk proteins by on-line high-performance liquid chromatography and electrospray ionization-mass spectrometry

Kappacin, a Novel Antibacterial Peptide from Bovine Milk

Healthy Multifunctional Spectra of Milk Glycoproteins and Their Fragments – a Review Article

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