Transglycosylation activities of bifidobacterial GHs

Bifidobacteria play an important role in the eco-physiology of the colonic microbiota. Human milk oligosaccharides (HMO) are prominent among the functional components of human milk. HMO selectively support the growth and activity of desired bacteria in the infant intestine, thus they have prebiotic or bifidogenic effects since bifidobacteria dominate in the gut of breast-fed infants. Infant-associated Bifidobacterium species are equipped with genetic and enzymatic sets dedicated to the utilization of HMO. It will be interesting and also challenging to exploit transglycosylation activities of the glycoside hydrolases (GHs) from an infant gut-associated Bifidobacterium sp. involved in HMO degradation to synthesize HMO structures. The proposed project aims: (i) to investigate transglycosylation activities and the extent of glycosyl transfer of the selected glycoside hydrolases from an infant gut isolate (ii) to identify the function roles of the key residues in the active sites of these selected glycoside hydrolases; (iii) to synthesize the core, the precursor and the backbone structures of HMO using these glycoside hydrolases. The main innovative aspects are to exploit transglycosylation activities of the glycoside hydrolases from the infant gut isolate for the synthesis of HMO structures in vitro and to provide insights into the catalytic importance of the amino acids involved in transglycosylation in the active sites of these enzymes.

Bifidobacteria play an important role in the eco-physiology of the colonic microbiota. Human milk oligosaccharides (HMO) are prominent among the functional components of human milk. HMO selectively support the growth and activity of desired bacteria in the infant intestine, thus they have prebiotic or bifidogenic effects since bifidobacteria dominate in the gut of breast-fed infants. Infant-associated Bifidobacterium species are equipped with genetic and enzymatic sets dedicated to the utilization of HMO. It is interesting and also challenging to exploit transglycosylation activities of the glycoside hydrolases (GHs) from an infant gut-associated Bifidobacterium sp. involved in HMO degradation to synthesize HMO structures. The main innovative aspects are to exploit transglycosylation activities of the glycoside hydrolases from the infant gut isolate for the synthesis of HMO structures in vitro and to provide insights into the catalytic importance of the amino acids involved in transglycosylation in the active sites of these enzymes.