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Alphons G. J. Voragen - One of the best experts on this subject based on the ideXlab platform.
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Cloning and characterization of arabinoxylan arabinofuranohydrolase-D3 (AXHd3) from Bifidobacterium Adolescentis DSM20083.
Applied microbiology and biotechnology, 2005Co-Authors: L.a.m. Van Den Broek, Gerrit Beldman, Ruth M. Lloyd, Jan C. Verdoes, Barry Mccleary, Alphons G. J. VoragenAbstract:Arabinoxylan arabinofuranohydrolase-D3 (AXHd3) from Bifidobacterium Adolescentis releases only C3-linked arabinose residues from double-substituted xylose residues. A genomic library of B. Adolescentis DSM20083 was screened for the presence of the axhD3 gene. Two plasmids were identified containing part of the axhD3 gene. The nucleotide sequences were combined and three open reading frames (ORFs) were found. The first ORF showed high homology with xylanases belonging to family 8 of the glycoside hydrolases and this gene was designated xylA. The second ORF was the axhD3 gene belonging to glycoside hydrolase family 43. The third (partial) ORF coded for a putative carboxylesterase. The axhD3 gene was cloned and expressed in Escherichia coli. Several substrates were employed in the biochemical characterization of recombinant AXHd3. The enzyme showed the highest activity toward wheat arabinoxylan oligosaccharides. In addition, β-xylanase from Trichoderma sp. was able to degrade soluble wheat arabinoxylan polymer to a higher extent, after pretreatment with recombinant AXHd3. Arabinoxylan oligosaccharides incubated with a combination of recombinant AXHd3 and an α-l-arabinofuranosidase from Aspergillus niger did not result in a higher maximal release of arabinose than incubation with these enzymes separately.
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Glycosyl hydrolases from Bifidobacterium Adolescentis DSM20083. An overview
Le Lait, 2005Co-Authors: L.a.m. Van Den Broek, Gerrit Beldman, Sandra W.a. Hinz, Chantal H. L. Doeswijk-voragen, Jean-paul Vincken, Alphons G. J. VoragenAbstract:It is claimed that bifidobacteria have several health-promoting effects. To increase the amount of bifidobacteria in the colon the concept of probiotics and/or prebiotics can be applied. Bifi- dobacterium Adolescentis is one of the main species of bifidobacteria in the gastro-intestinal tract of human adults. B. Adolescentis is able to degrade a wide range of oligosaccharides and a number of glycosyl hydrolases have been characterized in detail. The hydrolytic activity of the glycosyl hydrolases from B. Adolescentis toward prebiotics like arabinoxylan-oligosaccharides, isomalto-oli- gosaccharides, arabinogalactan, and sucrose-based oligosaccharides (raffinose, stachyose, and fructo-oligosaccharides) is reviewed. Alternatively, some of these glycosyl hydrolases are able to catalyze transglycosylation, which allows them to elongate oligosaccharides and to prepare poten- tially prebiotic oligosaccharides. Such oligosaccharides might be used to influence the microbial composition in the more distal parts of the colon. In nature, not all enzyme-substrate encounters are transglycosylating. So, the hydrolytic activity of the enzyme makes the oligosaccharide elongation less efficient than desired. Site-directed mutagenesis was applied to improve the transglycosylation reaction of the α-galactosidase from B. Adolescentis. Bifidobacterium / prebiotic / glycosyl hydrolase / transglycosylation / site-directed mutagenesis Resume - Les glycosyl hydrolases de Bifidobacterium Adolescentis DSM20083. Il est affirme que les bifidobacteries ont des proprietes benefiques sur la sante. Pour augmenter la teneur en bifido- bacteries au niveau du colon, le concept de probiotiques et/ou prebiotiques peut etre applique. Bifidobacterium Adolescentis est l'une des principales especes de bifidobacteries dans le tractus gas- tro-intestinal des adultes. Certaines des glycosyl hydrolases de B. Adolescentis ont ete caracterisees en detail et elles semblent degrader un large eventail d'oligosaccharides. L'activite d'hydrolyse des glycosyl hydrolases de B. Adolescentis envers des prebiotiques tels que les arabino-xylanes, isomalto- oligosaccharides, arabino-galactanes et les oligosaccharides contenant du saccharose (raffinose, sta- chyose et fructo-oligosaccharides) est passee en revue. De plus, certaines de ces glycosyl hydrolases peuvent etre utilisees pour preparer des oligosaccharides prebiotiques potentiels par transglycosy- lation, ce qui permet d'allonger les oligosaccharides. De tels oligosaccharides peuvent etre utilises pour influencer la composition microbienne au niveau des parties plus distales du colon. Les pro- duits de rencontre enzymes-substrates ne sont pas tous transglycosyles naturellement et l'activite d'hydrolyse de l'enzyme entraine une elongation de l'oligosaccharide moindre que celle desiree. La mutagenese dirigee a ete appliquee pour ameliorer la reaction de transglycosylation de l'α-galactosi- dase de B. Adolescentis. Bifidobacterium / prebiotique / glycosyl hydrolases / transglycosylation / mutagenese dirigee
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Crystal structure of sucrose phosphorylase from Bifidobacterium Adolescentis.
Biochemistry, 2004Co-Authors: D. Sprogoe, Alphons G. J. Voragen, Osman Mirza, Jette S. Kastrup, Michael Gajhede, L.a.m. Van Den Broek, Lars K. SkovAbstract:Around 80 enzymes are implicated in the generic starch and sucrose pathways. One of these enzymes is sucrose phosphorylase, which reversibly catalyzes the conversion of sucrose and orthophosphate to d-Fructose and a-d-glucose 1-phosphate. Here, we present the crystal structure of sucrose phosphorylase from Bifidobacterium Adolescentis (BiSP) refined at 1.77 A resolution. It represents the first 3D structure of a sucrose phosphorylase and is the first structure of a phosphate-dependent enzyme from the glycoside hydrolase family 13. The structure of BiSP is composed of the four domains A, B, B‘, and C. Domain A comprises the (s/a)8-barrel common to family 13. The catalytic active-site residues (Asp192 and Glu232) are located at the tips of s-sheets 4 and 5 in the (s/a)8-barrel, as required for family 13 members. The topology of the B‘ domain disfavors oligosaccharide binding and reduces the size of the substrate access channel compared to other family 13 members, underlining the role of this domain in modulating the function of these enzymes. It is remarkable that the fold of the C domain is not observed in any other known hydrolases of family 13. BiSP was found as a homodimer in the crystal, and a dimer contact surface area of 960 A2 per monomer was calculated. The majority of the interactions are confined to the two B domains, but interactions between the loop 8 regions of the two barrels are also observed. This results in a large cavity in the dimer, including the entrance to the two active sites.
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Physico-chemical and transglucosylation properties of recombinant sucrose phosphorylase from Bifidobacterium Adolescentis DSM20083.
Applied microbiology and biotechnology, 2004Co-Authors: L.a.m. Van Den Broek, Gerrit Beldman, E.l. Van Boxtel, R.p. Kievit, René Verhoef, Alphons G. J. VoragenAbstract:Clones of a genomic library of Bifidobacterium Adolescentis were grown in minimal medium with sucrose as sole carbon source. An enzymatic fructose dehydrogenase assay was used to identify sucrose-degrading enzymes. Plasmids were isolated from the positive colonies and sequence analysis revealed that two types of insert were present, which only differed with respect to their orientation in the plasmid. An open reading frame of 1,515 nucleotides with high homology for sucrose phosphorylases was detected on these inserts. The gene was designated SucP and encoded a protein of 56,189 Da. SucP was heterologously expressed in Escherichia coli, purified, and characterized. The molecular mass of SucP was 58 kDa, as estimated by SDS-PAGE, while 129 kDa was found with gel permeation, suggesting that the native enzyme was a dimer. The enzyme showed high activity towards sucrose and a lower extent towards α-glucose-1-phosphate. The transglucosylation properties were investigated using a broad range of monomeric sugars as acceptor substrate for the recombinant enzyme, while α-glucose-1-phosphate served as donor. d- and l-arabinose, d- and l-arabitol, and xylitol showed the highest production of transglucosylation products. The investigated disaccharides and trisaccharides were not suitable as acceptors. The structure of the transglucosylation product obtained with d-arabinose as acceptor was elucidated by NMR. The structure of the synthesized non-reducing dimer was α-Glcp(1→1)β-Araf.
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Cloning and characterization of two a-glucosidases from Bifidobacterium Adolescentis DSM20083
Applied microbiology and biotechnology, 2003Co-Authors: L.a.m. Van Den Broek, Jan Cornelis Verdoes, Gerrit Beldman, K. Struijs, Alphons G. J. VoragenAbstract:Two a-glucosidase encoding genes (aglA and aglB) from Bifidobacterium Adolescentis DSM 20083 were isolated and characterized. Both a-glucosidases belong to family 13 of the glycosyl hydrolases. Recom- binant AglA (EC 3.2.1.10) and AglB (EC 3.2.1.20), expressed in Escherichia coli, showed high hydrolytic activity towards isomaltose and pnp-a-glucoside. The Km for pnp-a-glucoside was 1.05 and 0.47 mM and the Vmax was 228 and 113 U mg -1 for AglA and AglB, respec- tively. Using pnp-a-glucoside as substrate, the pH optimum for AglA was 6.6 and the temperature optimum was 37�C. For AglB, values of pH 6.8 and 47�C were found. AglA also showed high hydrolytic activity towards isomaltotriose and, to a lesser extent, towards trehalose. AglB has a high preference for maltose and less activity towards sucrose; minor activity was observed towards melizitose, low molecular weight dextrin, maltitol, and maltotriose. The recombinant a-glucosidases were tested for their transglucosylation activity. AglA was able to synthesize oligosaccharides from trehalose and sucrose. AglB formed oligosaccharides from sucrose, maltose, and melizitose.
L.a.m. Van Den Broek - One of the best experts on this subject based on the ideXlab platform.
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Crystal structure of sucrose phosphorylase from Bifidobacterium Adolescentis.
Biochemistry, 2004Co-Authors: D. Sprogoe, Alphons G. J. Voragen, Osman Mirza, Jette S. Kastrup, Michael Gajhede, L.a.m. Van Den Broek, Lars K. SkovAbstract:Around 80 enzymes are implicated in the generic starch and sucrose pathways. One of these enzymes is sucrose phosphorylase, which reversibly catalyzes the conversion of sucrose and orthophosphate to d-Fructose and a-d-glucose 1-phosphate. Here, we present the crystal structure of sucrose phosphorylase from Bifidobacterium Adolescentis (BiSP) refined at 1.77 A resolution. It represents the first 3D structure of a sucrose phosphorylase and is the first structure of a phosphate-dependent enzyme from the glycoside hydrolase family 13. The structure of BiSP is composed of the four domains A, B, B‘, and C. Domain A comprises the (s/a)8-barrel common to family 13. The catalytic active-site residues (Asp192 and Glu232) are located at the tips of s-sheets 4 and 5 in the (s/a)8-barrel, as required for family 13 members. The topology of the B‘ domain disfavors oligosaccharide binding and reduces the size of the substrate access channel compared to other family 13 members, underlining the role of this domain in modulating the function of these enzymes. It is remarkable that the fold of the C domain is not observed in any other known hydrolases of family 13. BiSP was found as a homodimer in the crystal, and a dimer contact surface area of 960 A2 per monomer was calculated. The majority of the interactions are confined to the two B domains, but interactions between the loop 8 regions of the two barrels are also observed. This results in a large cavity in the dimer, including the entrance to the two active sites.
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Physico-chemical and transglucosylation properties of recombinant sucrose phosphorylase from Bifidobacterium Adolescentis DSM20083.
Applied microbiology and biotechnology, 2004Co-Authors: L.a.m. Van Den Broek, Gerrit Beldman, E.l. Van Boxtel, R.p. Kievit, René Verhoef, Alphons G. J. VoragenAbstract:Clones of a genomic library of Bifidobacterium Adolescentis were grown in minimal medium with sucrose as sole carbon source. An enzymatic fructose dehydrogenase assay was used to identify sucrose-degrading enzymes. Plasmids were isolated from the positive colonies and sequence analysis revealed that two types of insert were present, which only differed with respect to their orientation in the plasmid. An open reading frame of 1,515 nucleotides with high homology for sucrose phosphorylases was detected on these inserts. The gene was designated SucP and encoded a protein of 56,189 Da. SucP was heterologously expressed in Escherichia coli, purified, and characterized. The molecular mass of SucP was 58 kDa, as estimated by SDS-PAGE, while 129 kDa was found with gel permeation, suggesting that the native enzyme was a dimer. The enzyme showed high activity towards sucrose and a lower extent towards α-glucose-1-phosphate. The transglucosylation properties were investigated using a broad range of monomeric sugars as acceptor substrate for the recombinant enzyme, while α-glucose-1-phosphate served as donor. d- and l-arabinose, d- and l-arabitol, and xylitol showed the highest production of transglucosylation products. The investigated disaccharides and trisaccharides were not suitable as acceptors. The structure of the transglucosylation product obtained with d-arabinose as acceptor was elucidated by NMR. The structure of the synthesized non-reducing dimer was α-Glcp(1→1)β-Araf.
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Cloning and characterization of two a-glucosidases from Bifidobacterium Adolescentis DSM20083
Applied microbiology and biotechnology, 2003Co-Authors: L.a.m. Van Den Broek, Jan Cornelis Verdoes, Gerrit Beldman, K. Struijs, Alphons G. J. VoragenAbstract:Two a-glucosidase encoding genes (aglA and aglB) from Bifidobacterium Adolescentis DSM 20083 were isolated and characterized. Both a-glucosidases belong to family 13 of the glycosyl hydrolases. Recom- binant AglA (EC 3.2.1.10) and AglB (EC 3.2.1.20), expressed in Escherichia coli, showed high hydrolytic activity towards isomaltose and pnp-a-glucoside. The Km for pnp-a-glucoside was 1.05 and 0.47 mM and the Vmax was 228 and 113 U mg -1 for AglA and AglB, respec- tively. Using pnp-a-glucoside as substrate, the pH optimum for AglA was 6.6 and the temperature optimum was 37�C. For AglB, values of pH 6.8 and 47�C were found. AglA also showed high hydrolytic activity towards isomaltotriose and, to a lesser extent, towards trehalose. AglB has a high preference for maltose and less activity towards sucrose; minor activity was observed towards melizitose, low molecular weight dextrin, maltitol, and maltotriose. The recombinant a-glucosidases were tested for their transglucosylation activity. AglA was able to synthesize oligosaccharides from trehalose and sucrose. AglB formed oligosaccharides from sucrose, maltose, and melizitose.
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Purification and mode of action of two different arabinoxylan arabinofuranohydrolases from Bifidobacterium Adolescentis DSM 20083
Applied Microbiology and Biotechnology, 1999Co-Authors: K M J Van Laere, Gerrit Beldman, L.a.m. Van Den Broek, C. H. L. Voragen, T. Kroef, Alphons G. J. VoragenAbstract:Two novel arabinofuranohydrolases (AXH-d3 and AXH-m23) were purified from Bifidobacterium Adolescentis DSM 20083. Both enzymes were induced upon growth of Bi. Adolescentis on xylose and arabinoxylan-derived oligosaccharides. They were only active with arabinoxylans and therefore denoted as arabinoxylan arabinofuranohydrolases. Their optimal activity was at pH 6 and 30–40 °C. They were very specific in their mode of action and were clearly different from AXH-m from Aspergillus awamori. AXH-m23 released only arabinosyl groups, which were linked to the C-2 or C-3 position of singly substituted xylose residues in arabinoxylan oligomers. AXH-d3 hydrolysed C-3-linked arabinofuranosyl residues of doubly substituted xylopyranosyl residues of arabinoxylans and arab- inoxylan-derived oligosaccharides. No activity was observed with C-2-linked arabinofuranosyl residues of these doubly substituted xylopyranosyl residues, or against C-2- and C-3-linked arabinofuranosyl residues of singly substituted xylopyranosyl residues. The combination of AXH-d3 and AXH-m showed low debranching activity with highly substituted glucurono-arabinoxylans. However, arabinoxylan from wheat flour was debranched almost completely.
Gerrit Beldman - One of the best experts on this subject based on the ideXlab platform.
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Structural Rearrangements of Sucrose Phosphorylase from Bifidobacterium Adolescentis during Sucrose Conversion
The Journal of biological chemistry, 2006Co-Authors: Osman Mirza, L.a.m. Van Den Broek, Gerrit Beldman, Lars K. Skov, D. Sprogoe, Jette S. Kastrup, Michael GajhedeAbstract:Abstract The reaction mechanism of sucrose phosphorylase from Bifidobacterium Adolescentis (BiSP) was studied by site-directed mutagenesis and x-ray crystallography. An inactive mutant of BiSP (E232Q) was co-crystallized with sucrose. The structure revealed a substrate-binding mode comparable with that seen in other related sucrose-acting enzymes. Wild-type BiSP was also crystallized in the presence of sucrose. In the dimeric structure, a covalent glucosyl intermediate was formed in one molecule of the BiSP dimer, and after hydrolysis of the glucosyl intermediate, a β-d-glucose product complex was formed in the other molecule. Although the overall structure of the BiSP-glucosyl intermediate complex is similar to that of the BiSP(E232Q)-sucrose complex, the glucose complex discloses major differences in loop conformations. Two loops (residues 336-344 and 132-137) in the proximity of the active site move up to 16 and 4A, respectively. On the basis of these findings, we have suggested a reaction cycle that takes into account the large movements in the active-site entrance loops.
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Cloning and characterization of arabinoxylan arabinofuranohydrolase-D3 (AXHd3) from Bifidobacterium Adolescentis DSM20083.
Applied microbiology and biotechnology, 2005Co-Authors: L.a.m. Van Den Broek, Gerrit Beldman, Ruth M. Lloyd, Jan C. Verdoes, Barry Mccleary, Alphons G. J. VoragenAbstract:Arabinoxylan arabinofuranohydrolase-D3 (AXHd3) from Bifidobacterium Adolescentis releases only C3-linked arabinose residues from double-substituted xylose residues. A genomic library of B. Adolescentis DSM20083 was screened for the presence of the axhD3 gene. Two plasmids were identified containing part of the axhD3 gene. The nucleotide sequences were combined and three open reading frames (ORFs) were found. The first ORF showed high homology with xylanases belonging to family 8 of the glycoside hydrolases and this gene was designated xylA. The second ORF was the axhD3 gene belonging to glycoside hydrolase family 43. The third (partial) ORF coded for a putative carboxylesterase. The axhD3 gene was cloned and expressed in Escherichia coli. Several substrates were employed in the biochemical characterization of recombinant AXHd3. The enzyme showed the highest activity toward wheat arabinoxylan oligosaccharides. In addition, β-xylanase from Trichoderma sp. was able to degrade soluble wheat arabinoxylan polymer to a higher extent, after pretreatment with recombinant AXHd3. Arabinoxylan oligosaccharides incubated with a combination of recombinant AXHd3 and an α-l-arabinofuranosidase from Aspergillus niger did not result in a higher maximal release of arabinose than incubation with these enzymes separately.
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Glycosyl hydrolases from Bifidobacterium Adolescentis DSM20083. An overview
Le Lait, 2005Co-Authors: L.a.m. Van Den Broek, Gerrit Beldman, Sandra W.a. Hinz, Chantal H. L. Doeswijk-voragen, Jean-paul Vincken, Alphons G. J. VoragenAbstract:It is claimed that bifidobacteria have several health-promoting effects. To increase the amount of bifidobacteria in the colon the concept of probiotics and/or prebiotics can be applied. Bifi- dobacterium Adolescentis is one of the main species of bifidobacteria in the gastro-intestinal tract of human adults. B. Adolescentis is able to degrade a wide range of oligosaccharides and a number of glycosyl hydrolases have been characterized in detail. The hydrolytic activity of the glycosyl hydrolases from B. Adolescentis toward prebiotics like arabinoxylan-oligosaccharides, isomalto-oli- gosaccharides, arabinogalactan, and sucrose-based oligosaccharides (raffinose, stachyose, and fructo-oligosaccharides) is reviewed. Alternatively, some of these glycosyl hydrolases are able to catalyze transglycosylation, which allows them to elongate oligosaccharides and to prepare poten- tially prebiotic oligosaccharides. Such oligosaccharides might be used to influence the microbial composition in the more distal parts of the colon. In nature, not all enzyme-substrate encounters are transglycosylating. So, the hydrolytic activity of the enzyme makes the oligosaccharide elongation less efficient than desired. Site-directed mutagenesis was applied to improve the transglycosylation reaction of the α-galactosidase from B. Adolescentis. Bifidobacterium / prebiotic / glycosyl hydrolase / transglycosylation / site-directed mutagenesis Resume - Les glycosyl hydrolases de Bifidobacterium Adolescentis DSM20083. Il est affirme que les bifidobacteries ont des proprietes benefiques sur la sante. Pour augmenter la teneur en bifido- bacteries au niveau du colon, le concept de probiotiques et/ou prebiotiques peut etre applique. Bifidobacterium Adolescentis est l'une des principales especes de bifidobacteries dans le tractus gas- tro-intestinal des adultes. Certaines des glycosyl hydrolases de B. Adolescentis ont ete caracterisees en detail et elles semblent degrader un large eventail d'oligosaccharides. L'activite d'hydrolyse des glycosyl hydrolases de B. Adolescentis envers des prebiotiques tels que les arabino-xylanes, isomalto- oligosaccharides, arabino-galactanes et les oligosaccharides contenant du saccharose (raffinose, sta- chyose et fructo-oligosaccharides) est passee en revue. De plus, certaines de ces glycosyl hydrolases peuvent etre utilisees pour preparer des oligosaccharides prebiotiques potentiels par transglycosy- lation, ce qui permet d'allonger les oligosaccharides. De tels oligosaccharides peuvent etre utilises pour influencer la composition microbienne au niveau des parties plus distales du colon. Les pro- duits de rencontre enzymes-substrates ne sont pas tous transglycosyles naturellement et l'activite d'hydrolyse de l'enzyme entraine une elongation de l'oligosaccharide moindre que celle desiree. La mutagenese dirigee a ete appliquee pour ameliorer la reaction de transglycosylation de l'α-galactosi- dase de B. Adolescentis. Bifidobacterium / prebiotique / glycosyl hydrolases / transglycosylation / mutagenese dirigee
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Glycosyl hydrolases from Bifidobacterium Adolescentis DSM20083. An overview
Le Lait, 2005Co-Authors: Lambertus A.m. Van Den Broek, Gerrit Beldman, Chantal H. L. Doeswijk-voragen, Jean-paul Vincken, Sandra W.a. Hinz, Alphons G.j. VoragenAbstract:It is claimed that bifidobacteria have several health-promoting effects. To increase the amount of bifidobacteria in the colon the concept of probiotics and/or prebiotics can be applied. Bifidobacterium Adolescentis is one of the main species of bifidobacteria in the gastro-intestinal tract of human adults. B. Adolescentis is able to degrade a wide range of oligosaccharides and a number of glycosyl hydrolases have been characterized in detail. The hydrolytic activity of the glycosyl hydrolases from B. Adolescentis toward prebiotics like arabinoxylan-oligosaccharides, isomalto-oligosaccharides, arabinogalactan, and sucrose-based oligosaccharides (raffinose, stachyose, and fructo-oligosaccharides) is reviewed. Alternatively, some of these glycosyl hydrolases are able to catalyze transglycosylation, which allows them to elongate oligosaccharides and to prepare potentially prebiotic oligosaccharides. Such oligosaccharides might be used to influence the microbial composition in the more distal parts of the colon. In nature, not all enzyme-substrate encounters are transglycosylating. So, the hydrolytic activity of the enzyme makes the oligosaccharide elongation less efficient than desired. Site-directed mutagenesis was applied to improve the transglycosylation reaction of the $\alpha$-galactosidase from B. Adolescentis.
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Physico-chemical and transglucosylation properties of recombinant sucrose phosphorylase from Bifidobacterium Adolescentis DSM20083.
Applied microbiology and biotechnology, 2004Co-Authors: L.a.m. Van Den Broek, Gerrit Beldman, E.l. Van Boxtel, R.p. Kievit, René Verhoef, Alphons G. J. VoragenAbstract:Clones of a genomic library of Bifidobacterium Adolescentis were grown in minimal medium with sucrose as sole carbon source. An enzymatic fructose dehydrogenase assay was used to identify sucrose-degrading enzymes. Plasmids were isolated from the positive colonies and sequence analysis revealed that two types of insert were present, which only differed with respect to their orientation in the plasmid. An open reading frame of 1,515 nucleotides with high homology for sucrose phosphorylases was detected on these inserts. The gene was designated SucP and encoded a protein of 56,189 Da. SucP was heterologously expressed in Escherichia coli, purified, and characterized. The molecular mass of SucP was 58 kDa, as estimated by SDS-PAGE, while 129 kDa was found with gel permeation, suggesting that the native enzyme was a dimer. The enzyme showed high activity towards sucrose and a lower extent towards α-glucose-1-phosphate. The transglucosylation properties were investigated using a broad range of monomeric sugars as acceptor substrate for the recombinant enzyme, while α-glucose-1-phosphate served as donor. d- and l-arabinose, d- and l-arabitol, and xylitol showed the highest production of transglucosylation products. The investigated disaccharides and trisaccharides were not suitable as acceptors. The structure of the transglucosylation product obtained with d-arabinose as acceptor was elucidated by NMR. The structure of the synthesized non-reducing dimer was α-Glcp(1→1)β-Araf.
Marco Ventura - One of the best experts on this subject based on the ideXlab platform.
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Allergic Patients with Long-Term Asthma Display Low Levels of Bifidobacterium Adolescentis
PloS one, 2016Co-Authors: Arancha Hevia, Miguel Gueimonde, Francesca Turroni, Christian Milani, Patricia López, Carmen D. Donado, Adriana Cuervo, Sonia González, Ana Suárez, Marco VenturaAbstract:Accumulated evidence suggests a relationship between specific allergic processes, such as atopic eczema in children, and an aberrant fecal microbiota. However, little is known about the complete microbiota profile of adult individuals suffering from asthma. We determined the fecal microbiota in 21 adult patients suffering allergic asthma (age 39.43 ± 10.98 years old) and compare it with the fecal microbiota of 22 healthy controls (age 39.29 ± 9.21 years old) using culture independent techniques. An Ion-Torrent 16S rRNA gene-based amplification and sequencing protocol was used to determine the fecal microbiota profile of the individuals. Sequence microbiota analysis showed that the microbial alpha-diversity was not significantly different between healthy and allergic individuals and no clear clustering of the samples was obtained using an unsupervised principal component analysis. However, the analysis of specific bacterial groups allowed us to detect significantly lower levels of bifidobacteria in patients with long-term asthma. Also, in allergic individuals the Bifidobacterium Adolescentis species prevailed within the bifidobacterial population. The reduction in the levels on bifidobacteria in patients with long-term asthma suggests a new target in allergy research and opens possibilities for the therapeutic modulation of the gut microbiota in this group of patients.
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Genomic characterization and transcriptional studies of the starch-utilizing strain Bifidobacterium Adolescentis 22L.
Applied and environmental microbiology, 2014Co-Authors: Sabrina Duranti, D. Van Sinderen, Francesca Turroni, Gabriele Andrea Lugli, Christian Milani, Alice Viappiani, Marta Mangifesta, Laura Gioiosa, Paola Palanza, Marco VenturaAbstract:Bifidobacteria are members of the gut microbiota, but the genetic basis for their adaptation to the human gut is poorly understood. The analysis of the 2,203,222-bp genome of Bifidobacterium Adolescentis 22L revealed a nutrient acquisition strategy that targets diet/plant-derived glycans, in particular starch and starch-like carbohydrates. Starch-like carbohydrates were shown to support the growth of B. Adolescentis 22L. Transcriptome profiling of 22L cultures grown under in vitro conditions or during colonization of the murine gut by RNA sequencing and quantitative real-time PCR assays revealed the expression of a set of chromosomal loci responsible for starch metabolism as well as for pilus production. Such extracellular structures include so-called sortase-dependent and type IVb pili, which may be involved in gut colonization of 22L through adhesion to extracellular matrix proteins.
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Exploration of the genomic diversity and core genome of the Bifidobacterium Adolescentis phylogenetic group by means of a polyphasic approach.
Applied and environmental microbiology, 2012Co-Authors: Sabrina Duranti, C. Milani, E. Foroni, F. Bottacini, M. Delledonne, D. Van Sinderen, Francesca Turroni, Fabio Dal Bello, Alberto Ferrarini, Marco VenturaAbstract:In the current work, we describe genome diversity and core genome sequences among representatives of three bifidobacterial species, i.e., Bifidobacterium Adolescentis, Bifidobacterium catenulatum, and Bifidobacterium pseudocatenulatum, by employing a polyphasic approach involving analysis of 16S rRNA gene and 16S-23S internal transcribed spacer (ITS) sequences, pulsed-field gel electrophoresis (PFGE), and comparative genomic hybridization (CGH) assays.
Sabrina Duranti - One of the best experts on this subject based on the ideXlab platform.
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Bifidobacterium Adolescentis as a key member of the human gut microbiota in the production of GABA.
Scientific reports, 2020Co-Authors: Sabrina Duranti, Gabriele Andrea Lugli, Christian Milani, Leonardo Mancabelli, Lorena Ruiz, Hector Tamés, Walter Mancino, Giulia Longhi, Luca Carnevali, Andrea SgoifoAbstract:Gamma aminobutyric acid (GABA) is the principal inhibitory neurotransmitter playing a key role in anxiety and depression disorders in mammals. Recent studies revealed that members of the gut microbiota are able to produce GABA modulating the gut-brain axis response. Among members of the human gut microbiota, bifidobacteria are well known to establish many metabolic and physiologic interactions with the host. In this study, we performed genome analyses of more than 1,000 bifidobacterial strains publicly available revealing that Bifidobacterium Adolescentis taxon might represent a model GABA producer in human gastrointestinal tract. Moreover, the in silico screening of human/animal metagenomic datasets showed an intriguing association/correlation between B. Adolescentis load and mental disorders such as depression and anxiety. Interestingly, in vitro screening of 82 B. Adolescentis strains allowed identifying two high GABA producers, i.e. B. Adolescentis PRL2019 and B. Adolescentis HD17T2H, which were employed in an in vivo trial in rats. Feeding Groningen rats with a supplementation of B. Adolescentis strains, confirmed the ability of these microorganisms to stimulate the in vivo production of GABA highlighting their potential implication in gut-brain axis interactions.
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Evaluation of genetic diversity among strains of the human gut commensal Bifidobacterium Adolescentis.
Scientific reports, 2016Co-Authors: Sabrina Duranti, Francesca Turroni, Gabriele Andrea Lugli, Christian Milani, Alice Viappiani, Marta Mangifesta, Leonardo Mancabelli, Chiara Ferrario, Borja Sánchez, Abelardo MargollesAbstract:Bifidobacteria are members of the human gut microbiota, being numerically dominant in the colon of infants, while also being prevalent in the large intestine of adults. In this study, we determined and analyzed the pan-genome of Bifidobacterium Adolescentis, which is one of many bacteria found in the human adult gut microbiota. In silico analysis of the genome sequences of eighteen B. Adolescentis strains isolated from various environments, such as human milk, human feces and bovine rumen, revealed a high level of genetic variability, resulting in an open pan-genome. Compared to other bifidobacterial taxa such as Bifidobacterium bifidum and Bifidobacterium breve, the more extensive B. Adolescentis pan-genome supports the hypothesis that the genetic arsenal of this taxon expanded so as to become more adaptable to the variable and changing ecological niche of the gut. These increased genetic capabilities are particularly evident for genes required for dietary glycan-breakdown.
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Genomic characterization and transcriptional studies of the starch-utilizing strain Bifidobacterium Adolescentis 22L.
Applied and environmental microbiology, 2014Co-Authors: Sabrina Duranti, D. Van Sinderen, Francesca Turroni, Gabriele Andrea Lugli, Christian Milani, Alice Viappiani, Marta Mangifesta, Laura Gioiosa, Paola Palanza, Marco VenturaAbstract:Bifidobacteria are members of the gut microbiota, but the genetic basis for their adaptation to the human gut is poorly understood. The analysis of the 2,203,222-bp genome of Bifidobacterium Adolescentis 22L revealed a nutrient acquisition strategy that targets diet/plant-derived glycans, in particular starch and starch-like carbohydrates. Starch-like carbohydrates were shown to support the growth of B. Adolescentis 22L. Transcriptome profiling of 22L cultures grown under in vitro conditions or during colonization of the murine gut by RNA sequencing and quantitative real-time PCR assays revealed the expression of a set of chromosomal loci responsible for starch metabolism as well as for pilus production. Such extracellular structures include so-called sortase-dependent and type IVb pili, which may be involved in gut colonization of 22L through adhesion to extracellular matrix proteins.
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Exploration of the genomic diversity and core genome of the Bifidobacterium Adolescentis phylogenetic group by means of a polyphasic approach.
Applied and environmental microbiology, 2012Co-Authors: Sabrina Duranti, C. Milani, E. Foroni, F. Bottacini, M. Delledonne, D. Van Sinderen, Francesca Turroni, Fabio Dal Bello, Alberto Ferrarini, Marco VenturaAbstract:In the current work, we describe genome diversity and core genome sequences among representatives of three bifidobacterial species, i.e., Bifidobacterium Adolescentis, Bifidobacterium catenulatum, and Bifidobacterium pseudocatenulatum, by employing a polyphasic approach involving analysis of 16S rRNA gene and 16S-23S internal transcribed spacer (ITS) sequences, pulsed-field gel electrophoresis (PFGE), and comparative genomic hybridization (CGH) assays.