Characterization of α-Galactooligosaccharides formed via Heterologous Expression of α- 2 Galactosidases from Lactobacillus reuteri in Lactococcus lactis

• Author(s) / Creator(s)

  • Wang, Yvonne
  • Black, Brenna A.
  • Curtis, Jonathan M.
  • Gänzle, Michael G.

• α-Galacto-oligosaccharides (α-GOS) are produced by transgalactosylation reactions of α-galactosidase (α-Gal) or by conversion of raffinose family oligosaccharides by levansucrase. Similarly to β-GOS, α-GOS have the potential to mimic glycan receptors on eukaryotic cells and act as molecular decoys to prevent bacterial infection; however, data on transgalactosylation reactions of α-Gal remain scarce. The α-Gal gene sequence from Lactobacillus reuteri was cloned into an α-Gal negative strain of Lactococcus lactis. Transgalactosylation reactions were achieved using crude cell extracts with melibiose or raffinose as galactosyl donor and fucose, N-acetylglucosamine or lactose as galactosyl acceptor. The composition, sequence and most linkage types of α-GOS formed with acceptors saccharides were determined by liquid chromatography-tandem mass spectrometry. α-Gal of Lactobacillus reuteri formed (1 → 3)-, (1 → 4)- or (1 → 6)-linked α-GOS but exhibited a preference for formation of (1 → 6)-linkages. Fucose, N-acetylglucosamine and lactose were suitable galactosyl acceptors for α-Gal of L. reuteri, resulting in formation of (1 → 3)-, (1 → 4)- or (1 → 6)-linked hetero-oligosaccharides. By determining the structural specificity of α-Gal and increasing the variation of oligosaccharides produced by introducing alternative acceptor sugars, this work supports further studies to assess α-GOS pathogen adhesion prevention in mammalian hosts.

• Date created

  2014-01-01

• Subjects / Keywords

  • Lactobacillus reuteri
  • galacto-oligosaccharides
  • hetero-oligosaccharides
  • α-galactosidase
  • LC/MS

• Type of Item

  Article (Draft / Submitted)

• DOI

  https://doi.org/10.7939/r3-xr8c-yx17

• License

  © Springer-Verlag Berlin Heidelberg 2013