Rapid milk group classification by 1H NMR analysis of Le and H epitopes in human milk oligosaccharide donor samples

Abstract

Human milk oligosaccharides (HMOs) are a major constituent of human breast milk and play an important role in reducing the risk of infections in infants. The structures of these HMOs show similarities with blood group antigens in protein glycosylation, in particular in relation to fucosylation in Lewis blood group-type epitopes, matching the maternal pattern. Previously, based on the Secretor and Lewis blood group system, four milk groups have been defined, i.e. Lewis-positive Secretors, Lewis-positive non-Secretors, Lewis-negative Secretors and Lewis-negative non-Secretors. Here, a rapid one-dimensional (1)H nuclear magnetic resonance (NMR) analysis method is presented that identifies the presence/absence of (α1-2)-, (α1-3)- and (α1-4)-linked fucose residues in HMO samples, affording the essential information to attribute different HMO samples to a specific milk group. The developed method is based on the NMR structural-reporter-group concept earlier established for glycoprotein glycans. Further evaluation of the data obtained from the analysis of 36 HMO samples shows that within each of the four milk groups the relative levels of the different fucosylation epitopes can greatly vary. The data also allow a separation of the Lewis-positive Secretor milk group into two sub-groups.

Correlating Infant Fecal Microbiota Composition and Human Milk Oligosaccharide Consumption by Microbiota of 1‐Month‐Old Breastfed Infants

“…The acidic HMOs were detected in all milk samples. These observations were close to those published before . Similar to the HMOs in breast milk samples, there was also a large variation in HMO concentrations in the infant feces.…”

“…The minimum, maximum, median, average, and standard deviation of the concentrations of each HMO, the HMO type (neutral, fucosylated, and sialylated), and the total amounts are summarized in Table . Total concentrations of the measured HMOs in milk ranged from 2.0 to 6.5 mg mL −1 and were lower than those reported in literature . We observed large individual variation in the HMO concentrations in both the maternal milk samples and in infant feces.…”

Bisecting Galactose as a Feature of N-Glycans of Wild-type and Mutant Caenorhabditis elegans

“…The strong shift for H-4 can be taken as confirmation for a bisecting residue on the core β-mannose and so shares a trend observed with data on a bisected mammalian glycan (36), while the data are not compatible with a C-2 modification. The presence of β- d -Gal p 4″ and some α- d -Gal p C linked to mannose as well as some α- l -Fuc p linked to galactose is shown by relevant chemical shifts typical for such residues [4.6-4.3 (34,36), 5.5-5.1 (37), and 5.3-5.2 ppm (38) respectively for the anomeric H-1]; for the latter, it is noteworthy that older NMR data was interpreted as showing α1,2-fucosylation of mannose (39), but our data overall indicate the presence of a bisecting Fucα1,2Gal motif. Indeed, the proton signals of the β- d -Gal p 4″ show the most pronounced shift variations, which may be caused by the fucose or methylfucose bound in substoichiometric amounts to this unit, while the α-galactose is assumed to be linked to position 2 of the α- d -Man p 4 .…”

LC‐MS/MS analysis of permethylated free oligosaccharides and N‐glycans derived from human, bovine, and goat milk samples

“…Most informative structural analysis of milk oligosaccharides have been conducted by NMR . Various combinations of different separation and detection methods have been utilized in milk oligosaccharides quantitative analysis.…”