A versatile and scalable strategy for glycoprofiling bifidobacterial consumption of human milk oligosaccharides.
Bottom Line: For quantitative consumption, deuterated and reduced human milk oligosaccharide (HMO) standards were used.A detailed analysis of consumption glycoprofiles indicated strain-specific capabilities towards differential metabolism of milk oligosaccharides.This method overcomes previous limitations in the quantitative, multi-strain analysis of bacterial metabolism of HMOs and represents a novel approach towards understanding bacterial consumption of complex prebiotic oligosaccharides.
Affiliation: Departments of Viticulture & Enology, Chemistry and Food Science & Technology, and Microbiology Graduate Group, University of California, Davis, CA 95616, USA.Show MeSH
Mentions: The highest growth was observed mainly among the B. infantis strains JCM 7009, JCM 7010, JCM 7007, JCM 7011 and ATCC 15697, respectively, for which a nearly complete consumption of all HMOs with a DP (degree of polymerization of the HMOs) ≤ 7 (m/z = 732.25, 878.31, 1097.39 and 1243.44) was observed (Table 1, Figs 2 and S1). Among these strains the HMO consumption patterns resulted in highly similar glycoprofiles and the total HMO utilization ranged between 87.15% and 84.08% (Table 1). Except ATCC 15697, the rest of the strains have been classified by ribotyping and RAPD‐PCR to belong to the infantis biovar (Sakata et al., 2002). Compared with other bifidobacterial species tested these B. infantis strains shows unique glycoprofiling patterns with very high metabolic capacity for HMOs. This is also clearly reflected in their growth kinetic analysis for having distinctly similar growth rates and the highest ODs achieved among all the tested strains. Deuterated and reduced milk oligosaccharides were added as internal standards (Fig. 3) and Glycolyzer was used to perform automatic calculations of D/H ratios which were used as metric for measuring specific oligosaccharide consumption. HPLC‐Chip/TOF‐MS analysis of B. infantis ATCC 15697 oligosaccharide consumption patterns confirmed previous MALDI‐FTICR‐MS data (LoCascio et al., 2007) indicating that among several HMOs available B. infantis consumes only specific glycans. The HPLC‐Chip/TOF‐MS system enabled the detailed HMO consumption analysis at the single isomer level revealing that B. infantis does not discriminate among isomers of the same HMO (Fig. 4).
Affiliation: Departments of Viticulture & Enology, Chemistry and Food Science & Technology, and Microbiology Graduate Group, University of California, Davis, CA 95616, USA.