Glycoprofiling Bifidobacterial Consumption of Galacto-Oligosaccharides by Mass Spectrometry Reveals Strain-Specific, Preferential Consumption of Glycans

Abstract

Galacto-oligosaccharides (GOS) are versatile food ingredients that possess prebiotic properties. However, at present there is a lack of precise analytical methods to demonstrate specific GOS consumption by bifidobacteria. To better understand the role of GOS as prebiotics, purified GOS (pGOS) without disaccharides and monosaccharides was prepared and used in bacterial fermentation experiments. Growth curves showed that all bifidobacteria assayed utilized and grew on pGOS preparations. We used a novel mass spectrometry approach involving matrix-assisted laser desorption ionization-Fourier transform ion cyclotron resonance (MALDI-FTICR) to determine the composition of oligosaccharides in GOS syrup preparations. MALDI-FTICR analysis of spent fermentation media demonstrated that there was preferential consumption of selected pGOS species by different bifidobacteria. The approach described here demonstrates that MALDI-FTICR is a rapid-throughput tool for comprehensive profiling of oligosaccharides in GOS mixtures. In addition, the selective consumption of certain GOS species by different bifidobacteria suggests a means for targeting prebiotics to enrich select bifidobacterial species.

Anaphylaxis to cow's milk formula containing short-chain galacto-oligosaccharide

“…scGOS (FrieslandCampina Domo) supplemented to the milk formulas CMF1 and CMF2, which triggered these allergic reactions in our patients, is prepared with a b-galactosidase derived from Bacillus circulans and is a well-characterized mixture of more than 50 different oligosaccharides. 15 These oligosaccharides are composed of 1 to 7 galactose units linked to a glucose molecule in proportion of DPs as follows: DP5 or greater, 6.6%; DP4, 10.8%; DP3, 22.1%; DP2, 37.4%; and DP1, 22.5%. 9 The b-glycosidic linkage between the monomer units is mainly the linear linkage 1/4 Gal, although other b-glycosidic linkages, among which are found branched linkages, can also include the following: 1/6 Gal, 1 /2 Glc, 1/3 Glc, 1/4 Glc, 1/6 Glc, 1/2 Gal, and 1/3 Gal.…”

Diverse galactooligosaccharides consumption by bifidobacteria: implications of β-galactosidase—LacS operon

“…At the same time, it is noteworthy that B. breve and B. longum utilized the small DP4 fraction of GOS-P in addition to the major DP3 fraction. Barboza et al used a novel mass spectrometry approach to profile the consumption of GOS by four bifidobacteria belonging to four different species, 34) reporting that infant-borne isolates were able to consume GOS species with a wide range of DPs, whereas adult-borne isolates exhibited more differential consumption of GOS species with selected DPs. It is conceivable that some of the infant-borne bifidobacteria, such as B. breve and B. bifidum, are more adapted to GOS with higher DPs, whereas the typical adult-borne bifidobacteria such as B. adolescentis are specialist DP3 GOS users.…”

Crystal Structures of a Glycoside Hydrolase Family 20 Lacto-N-biosidase from Bifidobacterium bifidum

“…Furthermore, the intracellular GH42 ␤-galactosidase Bga42A, which is distant from the HMO cluster, is highly specific for LNT and functions as the sole ␤-galactosidase acting on type I HMOs. In the HMO degradation system of this strain, it was suggested that low molecular weight HMOs (degree of polymerization ranging from 3 to 8) are directly imported into the cells by transporters and subsequently cleaved by intracellular GHs (70). This analysis as well as recent research on commensal bacteria is unveiling the different HMO consumption modes of bifidobacterial strains.…”