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Régis Nouaille - One of the best experts on this subject based on the ideXlab platform.
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Production of oligosaccharides and cellobionic acid by Fibrobacter succinogenes S85growing on sugars, cellulose and wheat straw
2009Co-Authors: Régis Nouaille, Maria Matulova, A.m. Delort, Vladimír Pätoprstý, Evelyne ForanoAbstract:Extracellular culture fluid of Fibrobacter succinogenes S85 grown on glucose, cellobiose, cellulose or wheat straw was analysed by 2D-NMR spectroscopy. Cellodextrins did not accumulate in the culture medium of cells grown on cellulose or straw. Maltodextrins and Maltodextrin-1P were identified in the culture medium of glucose, cellobiose and cellulose grown cells. New glucose derivatives were identified in the culture fluid under all the substrate conditions. In particular, a compound identified as cellobionic acid accumulated at high levels in the medium of F. succinogenes S85 cultures. The production of cellobionic acid (and cellobionolactone also identified) was very surprising in an anaerobic bacterium. The results suggest metabolic shifts when cells were growing on solid substrate cellulose or straw compared to soluble sugars.
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Production of oligosaccharides and cellobionic acid by Fibrobacter succinogenes S85 growing on sugars, cellulose and wheat straw
Applied Microbiology and Biotechnology, 2009Co-Authors: Régis Nouaille, Maria Matulova, Vladimír Pätoprstý, Anne-marie Delort, Evelyne ForanoAbstract:Extracellular culture fluid of Fibrobacter succinogenes S85 grown on glucose, cellobiose, cellulose or wheat straw was analysed by 2D-NMR spectroscopy. Cellodextrins did not accumulate in the culture medium of cells grown on cellulose or straw. Maltodextrins and Maltodextrin-1 P were identified in the culture medium of glucose, cellobiose and cellulose grown cells. New glucose derivatives were identified in the culture fluid under all the substrate conditions. In particular, a compound identified as cellobionic acid accumulated at high levels in the medium of F. succinogenes S85 cultures. The production of cellobionic acid (and cellobionolactone also identified) was very surprising in an anaerobic bacterium. The results suggest metabolic shifts when cells were growing on solid substrate cellulose or straw compared to soluble sugars.
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Oligosaccharide synthesis in Fibrobacter succinogenes S85 and its modulation by the substrate
FEBS Journal, 2005Co-Authors: Régis Nouaille, Maria Matulova, A.m. Delort, E. ForanoAbstract:In this article we compared the metabolism of phosphorylated and unphosphorylated oligosaccharides (cellodextrins and Maltodextrins) in Fibrobacter succinogenes S85 resting cells incubated with the following substrates: glucose; cellobiose; a mixture of glucose and cellobiose; and cellulose. Intracellular and extracellular media were analysed by 1H-NMR and by TLC. The first important finding is that no cellodextrins were found to accumulate in the extracellular media of cells, regardless of the substrate; this contrasts to what is generally reported in the literature. The second finding of this work is that Maltodextrins of degree of polymerization > 2 are synthesized regardless of the substrate, and can be used by the bacteria. Maltotriose plays a key role in this metabolism of Maltodextrin. Maltodextrin-1-phosphate was detected in all the incubations, and a new metabolite, corresponding to a phosphorylated glucose derivative, was produced in the extracellular medium when cells were incubated with cellulose. The accumulation of these phosphorylated sugars increased with the degree of polymerization of the substrate
Evelyne Forano - One of the best experts on this subject based on the ideXlab platform.
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Production of oligosaccharides and cellobionic acid by Fibrobacter succinogenes S85growing on sugars, cellulose and wheat straw
2009Co-Authors: Régis Nouaille, Maria Matulova, A.m. Delort, Vladimír Pätoprstý, Evelyne ForanoAbstract:Extracellular culture fluid of Fibrobacter succinogenes S85 grown on glucose, cellobiose, cellulose or wheat straw was analysed by 2D-NMR spectroscopy. Cellodextrins did not accumulate in the culture medium of cells grown on cellulose or straw. Maltodextrins and Maltodextrin-1P were identified in the culture medium of glucose, cellobiose and cellulose grown cells. New glucose derivatives were identified in the culture fluid under all the substrate conditions. In particular, a compound identified as cellobionic acid accumulated at high levels in the medium of F. succinogenes S85 cultures. The production of cellobionic acid (and cellobionolactone also identified) was very surprising in an anaerobic bacterium. The results suggest metabolic shifts when cells were growing on solid substrate cellulose or straw compared to soluble sugars.
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Production of oligosaccharides and cellobionic acid by Fibrobacter succinogenes S85 growing on sugars, cellulose and wheat straw
Applied Microbiology and Biotechnology, 2009Co-Authors: Régis Nouaille, Maria Matulova, Vladimír Pätoprstý, Anne-marie Delort, Evelyne ForanoAbstract:Extracellular culture fluid of Fibrobacter succinogenes S85 grown on glucose, cellobiose, cellulose or wheat straw was analysed by 2D-NMR spectroscopy. Cellodextrins did not accumulate in the culture medium of cells grown on cellulose or straw. Maltodextrins and Maltodextrin-1 P were identified in the culture medium of glucose, cellobiose and cellulose grown cells. New glucose derivatives were identified in the culture fluid under all the substrate conditions. In particular, a compound identified as cellobionic acid accumulated at high levels in the medium of F. succinogenes S85 cultures. The production of cellobionic acid (and cellobionolactone also identified) was very surprising in an anaerobic bacterium. The results suggest metabolic shifts when cells were growing on solid substrate cellulose or straw compared to soluble sugars.
Maria Matulova - One of the best experts on this subject based on the ideXlab platform.
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Production of oligosaccharides and cellobionic acid by Fibrobacter succinogenes S85growing on sugars, cellulose and wheat straw
2009Co-Authors: Régis Nouaille, Maria Matulova, A.m. Delort, Vladimír Pätoprstý, Evelyne ForanoAbstract:Extracellular culture fluid of Fibrobacter succinogenes S85 grown on glucose, cellobiose, cellulose or wheat straw was analysed by 2D-NMR spectroscopy. Cellodextrins did not accumulate in the culture medium of cells grown on cellulose or straw. Maltodextrins and Maltodextrin-1P were identified in the culture medium of glucose, cellobiose and cellulose grown cells. New glucose derivatives were identified in the culture fluid under all the substrate conditions. In particular, a compound identified as cellobionic acid accumulated at high levels in the medium of F. succinogenes S85 cultures. The production of cellobionic acid (and cellobionolactone also identified) was very surprising in an anaerobic bacterium. The results suggest metabolic shifts when cells were growing on solid substrate cellulose or straw compared to soluble sugars.
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Production of oligosaccharides and cellobionic acid by Fibrobacter succinogenes S85 growing on sugars, cellulose and wheat straw
Applied Microbiology and Biotechnology, 2009Co-Authors: Régis Nouaille, Maria Matulova, Vladimír Pätoprstý, Anne-marie Delort, Evelyne ForanoAbstract:Extracellular culture fluid of Fibrobacter succinogenes S85 grown on glucose, cellobiose, cellulose or wheat straw was analysed by 2D-NMR spectroscopy. Cellodextrins did not accumulate in the culture medium of cells grown on cellulose or straw. Maltodextrins and Maltodextrin-1 P were identified in the culture medium of glucose, cellobiose and cellulose grown cells. New glucose derivatives were identified in the culture fluid under all the substrate conditions. In particular, a compound identified as cellobionic acid accumulated at high levels in the medium of F. succinogenes S85 cultures. The production of cellobionic acid (and cellobionolactone also identified) was very surprising in an anaerobic bacterium. The results suggest metabolic shifts when cells were growing on solid substrate cellulose or straw compared to soluble sugars.
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Oligosaccharide synthesis in Fibrobacter succinogenes S85 and its modulation by the substrate
FEBS Journal, 2005Co-Authors: Régis Nouaille, Maria Matulova, A.m. Delort, E. ForanoAbstract:In this article we compared the metabolism of phosphorylated and unphosphorylated oligosaccharides (cellodextrins and Maltodextrins) in Fibrobacter succinogenes S85 resting cells incubated with the following substrates: glucose; cellobiose; a mixture of glucose and cellobiose; and cellulose. Intracellular and extracellular media were analysed by 1H-NMR and by TLC. The first important finding is that no cellodextrins were found to accumulate in the extracellular media of cells, regardless of the substrate; this contrasts to what is generally reported in the literature. The second finding of this work is that Maltodextrins of degree of polymerization > 2 are synthesized regardless of the substrate, and can be used by the bacteria. Maltotriose plays a key role in this metabolism of Maltodextrin. Maltodextrin-1-phosphate was detected in all the incubations, and a new metabolite, corresponding to a phosphorylated glucose derivative, was produced in the extracellular medium when cells were incubated with cellulose. The accumulation of these phosphorylated sugars increased with the degree of polymerization of the substrate
Nicolas Sauvageot - One of the best experts on this subject based on the ideXlab platform.
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Enzymes Required for Maltodextrin Catabolism in Enterococcus faecalis Exhibit Novel Activities
Applied and Environmental Microbiology, 2017Co-Authors: Philippe Joyet, Nicolas Sauvageot, Abdelhamid Mokhtari, Christian Magni, Martin Espariz, Axel Hartke, Josef Deutscher, Eliette Riboulet-bisson, Victor Blancato, Rebecca ParalesAbstract:Maltose and Maltodextrins are formed during the degradation of starch or glycogen. Maltodextrins are composed of a mixture of maltooligosaccharides formed by α-1,4- but also some α-1,6-linked glucosyl residues. The α-1,6-linked glucosyl residues are derived from branching points in the polysaccharides. In Enterococcus faecalis, maltotriose is mainly transported and phosphorylated by a phosphoenolpyruvate:carbohydrate phosphotransferase system. The formed maltotriose-6″-phosphate is intracellularly dephosphorylated by a specific phosphatase, MapP. In contrast, maltotetraose and longer maltooligosaccharides up to maltoheptaose are taken up without phosphorylation via the ATP binding cassette transporter MdxEFG-MsmX. We show that the maltose-producing Maltodextrin hydrolase MmdH (GenBank accession no. EFT41964) in strain JH2-2 catalyzes the first catabolic step of α-1,4-linked maltooligosaccharides. The purified enzyme converts even-numbered α-1,4-linked maltooligosaccharides (maltotetraose, etc.) into maltose and odd-numbered (maltotriose, etc.) into maltose and glucose. Inactivation of mmdH therefore prevents the growth of E. faecalis on maltooligosaccharides ranging from maltotriose to maltoheptaose. Surprisingly, MmdH also functions as a maltogenic α-1,6-glucosidase, because it converts the maltotriose isomer isopanose into maltose and glucose. In addition, E. faecalis contains a glucose-producing α-1,6-specific Maltodextrin hydrolase (GenBank accession no. EFT41963, renamed GmdH). This enzyme converts panose, another maltotriose isomer, into glucose and maltose. A gmdH mutant had therefore lost the capacity to grow on panose. The genes mmdH and gmdH are organized in an operon together with GenBank accession no. EFT41962 (renamed mmgT). Purified MmgT transfers glucosyl residues from one α-1,4-linked maltooligosaccharide molecule to another. For example, it catalyzes the disproportionation of maltotriose by transferring a glucosyl residue to another maltotriose molecule, thereby forming maltotetraose and maltose together with a small amount of maltopentaose.
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enzymes required for Maltodextrin catabolism in enterococcus faecalis exhibit novel activities
Applied and Environmental Microbiology, 2017Co-Authors: Philippe Joyet, Abdelhamid Mokhtari, Victor S Blancato, Christian Magni, Eliette Ribouletbisson, Martin Espariz, Axel Hartke, Josef Deutscher, Nicolas SauvageotAbstract:Maltose and Maltodextrins are formed during the degradation of starch or glycogen. Maltodextrins are composed of a mixture of maltooligosaccharides formed by α-1,4, but also some α-1,6-linked glucosyl residues. The latter are derived from branching points in the polysaccharides. In Enterococcus faecalis , maltotriose is mainly transported and phosphorylated by a phosphoenolpyruvate:carbohydrate phosphotransferase system. The formed maltotriose-6″-P is intracellularly dephosphorylated by a specific phosphatase, MapP. In contrast, maltotetraose and longer maltooligosaccharides up to maltoheptaose are taken up without phosphorylation via the ATP binding cassette transporter MdxEFG/MsmX. We show that the maltose-producing Maltodextrin hydrolase MmdH (EFT41964 in strain JH2-2) catalyzes the first catabolic step of α-1,4-linked maltooligosaccharides. The purified enzyme converts even-numbered α-1,4-linked maltooligosaccharides (maltotetraose, etc.) into maltose and odd-numbered (maltotriose, etc.) into maltose and glucose. Inactivation of mmdH therefore prevents growth of E. faecalis on maltooligosaccharides ranging from maltotriose to maltoheptaose. Surprisingly, MmdH also functions as maltogenic α-1,6-glucosidase, because it converts the maltotriose isomer isopanose into maltose and glucose. E. faecalis contains in addition a glucose-producing α-1,6-specific Maltodextrin hydrolase (EFT41963, renamed GmdH). This enzyme converts panose, another maltotriose isomer, into glucose and maltose. A gmdH mutant had therefore lost the capacity to grow on panose. The genes mmdH and gmdH are organized in an operon together with EFT41962 (renamed mmgT ). Purified MmgT transfers glucosyl residues from one α-1,4-linked maltooligosaccharide molecule to another. For example, it catalyzes the disproportionation of maltotriose by transferring a glucosyl residue to another maltotriose molecule thereby forming maltotetraose and maltose together with a small amount of maltopentaose. IMPORTANCE The utilization of Maltodextrins by Enterococcus faecalis has been shown to increase the virulence of this nosocomial pathogen. However, little is known about how this organism catabolizes Maltodextrins. We therefore identified the enzymes involved in the metabolism of various α-1,4- and α-1,6-linked maltooligosaccharides. We found that one of these enzymes functions as maltose-producing α-glucosidase with relaxed linkage specificity (α-1,4 and α-1,6) and exo- and endo-glucosidase activity. A third enzyme, which resembles amylomaltases, exclusively transfers glucosyl residues from one maltooligosaccharide molecule to another. Similar enzymes are present in numerous other Firmicutes, such as streptococci and lactobacilli, suggesting that these organisms follow the same maltose degradation pathway as E. faecalis .
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enterococcus faecalis uses a phosphotransferase system permease and a host colonization related abc transporter for Maltodextrin uptake
Journal of Bacteriology, 2017Co-Authors: Nicolas Sauvageot, Abdelhamid Mokhtari, Philippe Joyet, Aurelie Budinverneuil, Victor S Blancato, Guillermo D Repizo, Celine Henry, Andreas Pikis, John F ThompsonAbstract:Maltodextrin is a mixture of maltooligosaccharides, which are produced by the degradation of starch or glycogen. They are mostly composed of α-1,4- and some α-1,6-linked glucose residues. Genes presumed to code for the Enterococcus faecalis Maltodextrin transporter were induced during enterococcal infection. We therefore carried out a detailed study of Maltodextrin transport in this organism. Depending on their length (3 to 7 glucose residues), E. faecalis takes up Maltodextrins either via MalT, a maltose-specific permease of the phosphoenolpyruvate (PEP):carbohydrate phosphotransferase system (PTS), or the ATP binding cassette (ABC) transporter MdxEFG-MsmX. Maltotriose, the smallest Maltodextrin, is primarily transported by the PTS permease. A malT mutant therefore exhibits significantly reduced growth on maltose and maltotriose. The residual uptake of the trisaccharide is catalyzed by the ABC transporter, because a malT mdxF double mutant no longer grows on maltotriose. The trisaccharide arrives as maltotriose-6″-P in the cell. MapP, which dephosphorylates maltose-6'-P, also releases Pi from maltotriose-6″-P. Maltotetraose and longer Maltodextrins are mainly (or exclusively) taken up via the ABC transporter, because inactivation of the membrane protein MdxF prevents growth on maltotetraose and longer Maltodextrins up to at least maltoheptaose. E. faecalis also utilizes panose and isopanose, and we show for the first time, to our knowledge, that in contrast to maltotriose, its two isomers are primarily transported via the ABC transporter. We confirm that Maltodextrin utilization via MdxEFG-MsmX affects the colonization capacity of E. faecalis, because inactivation of mdxF significantly reduced enterococcal colonization and/or survival in kidneys and liver of mice after intraperitoneal infection.IMPORTANCE Infections by enterococci, which are major health care-associated pathogens, are difficult to treat due to their increasing resistance to clinically relevant antibiotics, and new strategies are urgently needed. A largely unexplored aspect is how these pathogens proliferate and which substrates they use in order to grow inside infected hosts. The use of Maltodextrins as a source of carbon and energy was studied in Enterococcus faecalis and linked to its virulence. Our results demonstrate that E. faecalis can efficiently use glycogen degradation products. We show here that depending on the length of the Maltodextrins, one of two different transporters is used: the maltose-PTS transporter MalT, or the MdxEFG-MsmX ABC transporter. MdxEFG-MsmX takes up longer Maltodextrins as well as complex molecules, such as panose and isopanose.
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Enterococcus faecalis Uses a Phosphotransferase System permease and a host colonization-related ABC transporter for Maltodextrin uptake
Journal of Bacteriology, 2017Co-Authors: Nicolas Sauvageot, Abdelhamid Mokhtari, Philippe Joyet, Victor S Blancato, Guillermo D Repizo, Celine Henry, Andreas Pikis, Aurélie Budin-verneuil, John Thompson, Christian MagniAbstract:Maltodextrin is a mixture of maltooligosaccharides, which are produced by the degradation of starch or glycogen. They are mostly composed of alpha-1,4- and some alpha-1,6-linked glucose residues. Genes presumed to code for the Enterococcus faecalis Maltodextrin transporter were induced during enterococcal infection. We therefore carried out a detailed study of Maltodextrin transport in this organism. Depending on their length (3 to 7 glucose residues), E. faecalis takes up Maltodextrins either via MalT, a maltose-specific permease of the phosphoenolpyruvate (PEP): carbohydrate phosphotransferase system (PTS), or the ATP binding cassette (ABC) transporter MdxEFG-MsmX. Maltotriose, the smallest Maltodextrin, is primarily transported by the PTS permease. A malT mutant therefore exhibits significantly reduced growth on maltose and maltotriose. The residual uptake of the trisaccharide is catalyzed by the ABC transporter, because a malT mdxF double mutant no longer grows on maltotriose. The trisaccharide arrives as maltotriose-6 ''-P in the cell. MapP, which dephosphorylates maltose-6'-P, also releases Pi from maltotriose-6 ''-P. Maltotetraose and longer Maltodextrins are mainly (or exclusively) taken up via the ABC transporter, because inactivation of the membrane protein MdxF prevents growth on maltotetraose and longer Maltodextrins up to at least maltoheptaose. E. faecalis also utilizes panose and isopanose, and we show for the first time, to our knowledge, that in contrast to maltotriose, its two isomers are primarily transported via the ABC transporter. We confirm that Maltodextrin utilization via MdxEFG-MsmX affects the colonization capacity of E. faecalis, because inactivation of mdxF significantly reduced enterococcal colonization and/or survival in kidneys and liver of mice after intraperitoneal infection. IMPORTANCE Infections by enterococci, which are major health care-associated pathogens, are difficult to treat due to their increasing resistance to clinically relevant antibiotics, and new strategies are urgently needed. A largely unexplored aspect is how these pathogens proliferate and which substrates they use in order to grow inside infected hosts. The use of Maltodextrins as a source of carbon and energy was studied in Enterococcus faecalis and linked to its virulence. Our results demonstrate that E. faecalis can efficiently use glycogen degradation products. We show here that depending on the length of the Maltodextrins, one of two different
E. Forano - One of the best experts on this subject based on the ideXlab platform.
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Oligosaccharide synthesis in Fibrobacter succinogenes S85 and its modulation by the substrate
FEBS Journal, 2005Co-Authors: Régis Nouaille, Maria Matulova, A.m. Delort, E. ForanoAbstract:In this article we compared the metabolism of phosphorylated and unphosphorylated oligosaccharides (cellodextrins and Maltodextrins) in Fibrobacter succinogenes S85 resting cells incubated with the following substrates: glucose; cellobiose; a mixture of glucose and cellobiose; and cellulose. Intracellular and extracellular media were analysed by 1H-NMR and by TLC. The first important finding is that no cellodextrins were found to accumulate in the extracellular media of cells, regardless of the substrate; this contrasts to what is generally reported in the literature. The second finding of this work is that Maltodextrins of degree of polymerization > 2 are synthesized regardless of the substrate, and can be used by the bacteria. Maltotriose plays a key role in this metabolism of Maltodextrin. Maltodextrin-1-phosphate was detected in all the incubations, and a new metabolite, corresponding to a phosphorylated glucose derivative, was produced in the extracellular medium when cells were incubated with cellulose. The accumulation of these phosphorylated sugars increased with the degree of polymerization of the substrate