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Henri Petitdemange - One of the best experts on this subject based on the ideXlab platform.

  • Both pH and Carbon Flux Influence the Level of Rubredoxin in Clostridium butyricum
    Current Microbiology, 2001
    Co-Authors: Emmanuel Guedon, P. Gerard, Bruno Charpentier, Christiane Branlant, Henri Petitdemange
    Abstract:

    The rubredoxin expression level in Clostridium butyricum DSM 5431 grown in continuous culture was monitored using primer extension analyses of the rub gene and a specific enzymatic assay of the iron-sulfur protein. In this way, we showed that variations in rubredoxin content and in rub mRNA level were influenced by the pH of the culture and were directly dependent on the carbon flux.

  • Both pH and carbon flux influence the level of rubredoxin in Clostridium butyricum
    Current Microbiology, 2001
    Co-Authors: Emmanuel Guedon, P. Gerard, Bruno Charpentier, Christiane Branlant, Henri Petitdemange
    Abstract:

    The rubredoxin expression level in Clostridium butyricum DSM 5431 grown in continuous culture was monitored using primer extension analyses of the rub gene and a specific enzymatic assay of the iron-sulfur protein. In this way, we showed that variations in rubredoxin content and in rub mRNA level were influenced by the pH of the culture and were directly dependent on the carbon flux. The maximum rubredoxin level reached 1227.3 pmol (mg of proteins)(-1) (i.e. 0.7% of the total protein content) under strictly anaerobic conditions when cells grew at pH 6.5 with an excess of glucose. In addition, primer extension analyses established that the control for all the variations observed operates at the level of gene transcription. Altogether, these results suggested a main function of rubredoxin in Clostridium butyricum independent of the protection against oxygen as has already been reported for Desulfovibrio gigas and Pyrococcus furiosus.

  • Distribution of the rubredoxin gene among the Clostridium butyricum species.
    Current Microbiology, 1999
    Co-Authors: P. Gerard, J. Amine, Guy Raval, Henri Petitdemange
    Abstract:

    With PCR methods, the rubredoxin gene was systematically identified among 11 strains of Clostridium butyricum; this ubiquity means major functions in the metabolism of the Clostridia. The 11 PCR products allowed deduction of a sequence of 26 amino acids corresponding to positions 11–36 of the rubredoxin. They all contained the tyrosines at positions 11 and 13 and the phenylalanine at position 30 characteristic of the rubredoxin, but differed at positions 14–17, 20, 25, 29, and 31, allowing determination of three types of rubredoxins among these 11 strains of C. butyricum.

  • Properties of allyl alcohol-resistant mutants of Clostridium butyricum grown on glycerol
    Applied and Environmental Microbiology, 1996
    Co-Authors: Samir Abbad Andaloussi, J. Amine, P. Gerard, E. Petitdemange, Henri Petitdemange
    Abstract:

    Mutants of Clostridium butyricum E5 exhibiting resistance to allyl alcohol which produced the same quantities of 1,3-propanediol as the wild-type strain but more acetate than butyrate were isolated. The acetate-butyrate formation plays a major function in the regulation of the internal redox balance. Allyl alcohol resistance can be attributed not to the loss of 1,3-propanediol dehydrogenase but to a shift in the reductive properties of the enzyme. The data support the view that cellular regulation is modified to avoid intracellular accumulation of 3-hydroxypropionaldehyde.

Alain Rimbault - One of the best experts on this subject based on the ideXlab platform.

  • Cleavage of L-leucine-containing dipeptides by Clostridium butyricum.
    Bioorganic & Medicinal Chemistry Letters, 1999
    Co-Authors: Nasser Khelifa, M.e. Brik, Annie-claude Tessedre, Hugues De Rocquigny, Bernard-pierre Roques, Jacques Courtieu, Alain Rimbault
    Abstract:

    The ability of Clostridium butyricum cultures to hydrolyze three L-leucine-containing dipeptides (Leu-Leu, Leu-Gly and Gly-Leu) in a synthetic minimal medium is demonstrated by using gas chromatography coupled with mass spectrometry. The 13C nuclear magnetic resonance and a labeled dipeptide L-[1-13C]Leu-Gly were used to confirm this activity.

  • synthesis of 2 hydroxy acid from 2 amino acid by Clostridium butyricum
    Bioorganic & Medicinal Chemistry Letters, 1998
    Co-Authors: Nasser Khelifa, Mariejose Butel, Alain Rimbault
    Abstract:

    Cultures of Clostridium butyricum type strain in synthetic medium supplemented with various L-2-amino acids revealed the presence of the corresponding 2-hydroxy acid. This metabolite is able to produce the polyester poly(2-hydroxyalkanoic acid). The bioconversion is not stereoselective since D-2-amino acids were also converted. Chiral GC analysis demonstrated that only D-enantiomer is formed from L-leucine.

Claire Kruger - One of the best experts on this subject based on the ideXlab platform.

P. Gerard - One of the best experts on this subject based on the ideXlab platform.

  • Both pH and Carbon Flux Influence the Level of Rubredoxin in Clostridium butyricum
    Current Microbiology, 2001
    Co-Authors: Emmanuel Guedon, P. Gerard, Bruno Charpentier, Christiane Branlant, Henri Petitdemange
    Abstract:

    The rubredoxin expression level in Clostridium butyricum DSM 5431 grown in continuous culture was monitored using primer extension analyses of the rub gene and a specific enzymatic assay of the iron-sulfur protein. In this way, we showed that variations in rubredoxin content and in rub mRNA level were influenced by the pH of the culture and were directly dependent on the carbon flux.

  • Both pH and carbon flux influence the level of rubredoxin in Clostridium butyricum
    Current Microbiology, 2001
    Co-Authors: Emmanuel Guedon, P. Gerard, Bruno Charpentier, Christiane Branlant, Henri Petitdemange
    Abstract:

    The rubredoxin expression level in Clostridium butyricum DSM 5431 grown in continuous culture was monitored using primer extension analyses of the rub gene and a specific enzymatic assay of the iron-sulfur protein. In this way, we showed that variations in rubredoxin content and in rub mRNA level were influenced by the pH of the culture and were directly dependent on the carbon flux. The maximum rubredoxin level reached 1227.3 pmol (mg of proteins)(-1) (i.e. 0.7% of the total protein content) under strictly anaerobic conditions when cells grew at pH 6.5 with an excess of glucose. In addition, primer extension analyses established that the control for all the variations observed operates at the level of gene transcription. Altogether, these results suggested a main function of rubredoxin in Clostridium butyricum independent of the protection against oxygen as has already been reported for Desulfovibrio gigas and Pyrococcus furiosus.

  • Distribution of the rubredoxin gene among the Clostridium butyricum species.
    Current Microbiology, 1999
    Co-Authors: P. Gerard, J. Amine, Guy Raval, Henri Petitdemange
    Abstract:

    With PCR methods, the rubredoxin gene was systematically identified among 11 strains of Clostridium butyricum; this ubiquity means major functions in the metabolism of the Clostridia. The 11 PCR products allowed deduction of a sequence of 26 amino acids corresponding to positions 11–36 of the rubredoxin. They all contained the tyrosines at positions 11 and 13 and the phenylalanine at position 30 characteristic of the rubredoxin, but differed at positions 14–17, 20, 25, 29, and 31, allowing determination of three types of rubredoxins among these 11 strains of C. butyricum.

  • Properties of allyl alcohol-resistant mutants of Clostridium butyricum grown on glycerol
    Applied and Environmental Microbiology, 1996
    Co-Authors: Samir Abbad Andaloussi, J. Amine, P. Gerard, E. Petitdemange, Henri Petitdemange
    Abstract:

    Mutants of Clostridium butyricum E5 exhibiting resistance to allyl alcohol which produced the same quantities of 1,3-propanediol as the wild-type strain but more acetate than butyrate were isolated. The acetate-butyrate formation plays a major function in the regulation of the internal redox balance. Allyl alcohol resistance can be attributed not to the loss of 1,3-propanediol dehydrogenase but to a shift in the reductive properties of the enzyme. The data support the view that cellular regulation is modified to avoid intracellular accumulation of 3-hydroxypropionaldehyde.

Zhanyu Zhao - One of the best experts on this subject based on the ideXlab platform.

  • in vitro evaluation on adherence and antimicrobial properties of a candidate probiotic Clostridium butyricum cb2 for farmed fish
    Journal of Applied Microbiology, 2008
    Co-Authors: Tianxing Wu, Honggang Tang, Z. Song, L. Zhang, Zhanyu Zhao
    Abstract:

    Aims:  To characterize the antimicrobial and adhesion ability of candidate probiotic Clostridium butyricum CB2 for farmed fish in vitro. Methods and Results:  The potential probiotic Cl. butyricum CB2 had been evaluated for its adhesion capacity and antagonistic effect against two fish pathogens Aeromonas hydrophila and Vibrio anguillarum by the intestinal cell model. In addition, the aggregation ability and antimicrobial property on agar plate were assayed. The results indicated that the candidate probiotic Cl. butyricum CB2 have strong adhesion property and a higher antagonistic activity to Aer. hydrophila and V. anguillarum both on agar plate and cell model. Clostridium butyricum showed a higher aggregation which might be the reasons for bacteria adhesion and antimicrobial activity. Conclusions:  The strain Cl. butyricum CB2 could be used as potential probiotic to inhibit pathogens growth and prevent their colonization in fish intestinal tract. Significance and Impact of the Study:  This study revealed the antimicrobial and adhesion characteristic of Cl. butyricum CB2 which was selected as the potential probiotic to farmed fish.