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Corinne Rouland-lefèvre - One of the best experts on this subject based on the ideXlab platform.
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Gut-specific actinobacterial community structure and diversity associated with the wood-feeding termite species, Nasutitermes corniger (Motschulsky) described by nested PCR-DGGE analysis
Insectes Sociaux, 2009Co-Authors: T. Lefebvre, E. Miambi, Alejandro Pando, Madiop Diouf, Corinne Rouland-lefèvreAbstract:This comprehensive survey studied the actinobacterial community structure and putative representative members associated with the gut of the wood-feeding termite, Nasutitermes corniger (Motschulsky), using nested PCR-DGGE and 16S rDNA sequences analyses. The closest relatives of the actinobacteria inhabiting the gut of Nasutitermes corniger were in five families, regardless of the geographical origin of the termite colony: Propionibacteriaceae, Streptomycetaceae, Cellulomonodaceae, Corynebacteriaceae and Rubrobacteraceae . Feeding termites on beech wood did not result in substantial changes in the actinobacterial community structure as revealed by DGGE banding patterns. Most of the 16S rDNA sequences obtained after excision and sequencing of DGGE bands clustered with those previously retrieved in termite guts. These results confirm the presence of gut-specific actinobacteria. Except for the 16S rDNA sequences affiliated to Streptomycetaceae and Cellulomonodaceae , no sequence had more than 97% similarity with the closest isolated strains, indicating the presence of microorganisms that have not yet been cultivated. These results suggest that members of the Actinomycetales order account for the largest proportion of the Actinobacteria phylum inhabiting the gut of the termite N. corniger .
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Gut-specific actinobacterial community structure and diversity associated with the wood-feeding termite species, Nasutitermes corniger (Motschulsky) described by nested PCR-DGGE analysis
Insectes Sociaux, 2009Co-Authors: T. Lefebvre, E. Miambi, Alejandro Pando, Madiop Diouf, Corinne Rouland-lefèvreAbstract:This comprehensive survey studied the actinobacterial community structure and putative representative members associated with the gut of the wood-feeding termite, Nasutitermes corniger (Motschulsky), using nested PCR-DGGE and 16S rDNA sequences analyses. The closest relatives of the actinobacteria inhabiting the gut of Nasutitermes corniger were in five families, regardless of the geographical origin of the termite colony: Propionibacteriaceae, Streptomycetaceae, Cellulomonodaceae, Corynebacteriaceae and Rubrobacteraceae . Feeding termites on beech wood did not result in substantial changes in the actinobacterial community structure as revealed by DGGE banding patterns. Most of the 16S rDNA sequences obtained after excision and sequencing of DGGE bands clustered with those previously retrieved in termite guts. These results confirm the presence of gut-specific actinobacteria. Except for the 16S rDNA sequences affiliated to Streptomycetaceae and Cellulomonodaceae , no sequence had more than 97% similarity with the closest isolated strains, indicating the presence of microorganisms that have not yet been cultivated. These results suggest that members of the Actinomycetales order account for the largest proportion of the Actinobacteria phylum inhabiting the gut of the termite N. corniger .
Pierre-edouard Fournier - One of the best experts on this subject based on the ideXlab platform.
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Genome sequence and description of Corynebacterium ihumii sp. nov.
Standards in Genomic Sciences, 2014Co-Authors: Roshan Padmanabhan, Grégory Dubourg, Jean-christophe Lagier, Carine Couderc, Caroline Michelle, Didier Raoult, Pierre-edouard FournierAbstract:Corynebacterium ihumii strain GD7^T sp. nov. is proposed as the type strain of a new species, which belongs to the family Corynebacteriaceae of the class Actinobacteria . This strain was isolated from the fecal flora of a 62 year-old male patient, as a part of the culturomics study. _Corynebacterium ihumii is a Gram positive, facultativly anaerobic, nonsporulating bacillus. Here, we describe the features of this organism, together with the high quality draft genome sequence, annotation and the comparison with other member of the genus Corynebacteria . C. ihumii genome is 2,232,265 bp long (one chromosome but no plasmid) containing 2,125 protein-coding and 53 RNA genes, including 4 rRNA genes. The whole-genome shotgun sequence of _Corynebacterium ihumii strain GD7^T sp. nov has been deposited in EMBL under accession number GCA_000403725.
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Genome sequence and description of Corynebacterium ihumii sp. nov.
Standards in genomic sciences, 2014Co-Authors: Roshan Padmanabhan, Grégory Dubourg, Jean-christophe Lagier, Carine Couderc, Caroline Michelle, Didier Raoult, Pierre-edouard FournierAbstract:Corynebacterium ihumii strain GD7T sp. nov. is proposed as the type strain of a new species, which belongs to the family Corynebacteriaceae of the class Actinobacteria. This strain was isolated from the fecal flora of a 62 year-old male patient, as a part of the culturomics study. _Corynebacterium ihumii is a Gram positive, facultativly anaerobic, nonsporulating bacillus. Here, we describe the features of this organism, together with the high quality draft genome sequence, annotation and the comparison with other member of the genus Corynebacteria. C. ihumii genome is 2,232,265 bp long (one chromosome but no plasmid) containing 2,125 protein-coding and 53 RNA genes, including 4 rRNA genes. The whole-genome shotgun sequence of _Corynebacterium ihumii strain GD7T sp. nov has been deposited in EMBL under accession number GCA_000403725.
Lothar Eggeling - One of the best experts on this subject based on the ideXlab platform.
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Corynebacterium glutamicum harbours a molybdenum cofactor-dependent formate dehydrogenase which alleviates growth inhibition in the presence of formate
Microbiology, 2012Co-Authors: Sabrina Witthoff, Lothar Eggeling, Michael Bott, Tino PolenAbstract:Here, we show that Corynebacterium glutamicum ATCC 13032 co-metabolizes formate when it is grown with glucose as the carbon and energy source. CO2 measurements during bioreactor cultivation and use of 13C-labelled formate demonstrated that formate is almost completely oxidized to CO2. The deletion of fdhF (cg0618), annotated as formate dehydrogenase (FDH) and located in a cluster of genes conserved in the family Corynebacteriaceae, prevented formate utilization. Similarly, deletion of fdhD (cg0616) resulted in the inability to metabolize formate and deletion of cg0617 markedly reduced formate utilization. These results illustrated that all three gene products are required for FDH activity. Growth studies with molybdate and tungstate indicated that the FDH from C. glutamicum ATCC 13032 is a molybdenum-dependent enzyme. The presence of 100 mM formate caused a 25 % lowered growth rate during cultivation of C. glutamicum ATCC 13032 wild-type in glucose minimal medium. This inhibitory effect was increased in the strains lacking FDH activity. Our data demonstrate that C. glutamicum ATCC 13032 possesses an FDH with a currently unknown electron acceptor. The presence of the FDH might help the soil bacterium C. glutamicum ATCC 13032 to alleviate growth retardation caused by formate, which is ubiquitously present in the environment.
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The TetR-type transcriptional regulator FasR of Corynebacterium glutamicum controls genes of lipid synthesis during growth on acetate
Molecular Microbiology, 2010Co-Authors: Jens Nickel, Kristina Irzik, Jan Van Ooyen, Lothar EggelingAbstract:The addition of fatty acids to either Escherichia coli or Bacillus subtilis elicits an elaborate cellular response of the lipid metabolism. We found that in Corynebacterium glutamicum the expression of accD1 encoding the β-subunit of the essential acetyl-CoA carboxylase is repressed in acetate-grown cells without the addition of fatty acids. The TetR-type transcriptional regulator NCgl2404, termed FasR, was identified and deleted. During growth on acetate, but not on glucose, 17 genes are differentially expressed in the deletion mutant, among them accD1, and fasA and fasB both encoding fatty acid synthases, which were upregulated. Determination of the 5' ends of accD1, fasA, fasB and accBC together with the use of isolated FasR protein identified the FasR binding site, fasO, which is located within the accD1 and fasA transcript initiation site thus blocking transcription by RNA polymerase binding directly. The identified fasO motif is present in C. efficiens or C. diphtheriae, too, and it is actually similarly positioned in these bacteria within the 5' ends of the accD1 and fasA transcripts, and a fasR orthologue is also present. The identification of the FasR-fasO system in Corynebacteriaceae might indicate a conserved transcriptional control of the unique lipid synthesis in these mycolic acid-containing bacteria
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the two carboxylases of corynebacterium glutamicum essential for fatty acid and mycolic acid synthesis
Journal of Bacteriology, 2007Co-Authors: Roland Gande, Lynn G Dover, Karin Krumbach, Gurdyal S Besra, Hermann Sahm, Tadao Oikawa, Lothar EggelingAbstract:The suborder Corynebacterianeae comprises bacteria like Mycobacterium tuberculosis and Corynebacterium glutamicum, and these bacteria contain in addition to the linear fatty acids, unique α-branched β-hydroxy fatty acids, called mycolic acids. Whereas acetyl-coenzyme A (CoA) carboxylase activity is required to provide malonyl-CoA for fatty acid synthesis, a new type of carboxylase is apparently additionally present in these bacteria. It activates the α-carbon of a linear fatty acid by carboxylation, thus enabling its decarboxylative condensation with a second fatty acid to afford mycolic acid synthesis. We now show that the acetyl-CoA carboxylase of C. glutamicum consists of the biotinylated α-subunit AccBC, the β-subunit AccD1, and the small peptide AccE of 8.9 kDa, forming an active complex of approximately 812,000 Da. The carboxylase involved in mycolic acid synthesis is made up of the two highly similar β-subunits AccD2 and AccD3 and of AccBC and AccE, the latter two identical to the subunits of the acetyl-CoA carboxylase complex. Since AccD2 and AccD3 orthologues are present in all Corynebacterianeae, these polypeptides are vital for mycolic acid synthesis forming the unique hydrophobic outer layer of these bacteria, and we speculate that the two β-subunits present serve to lend specificity to this unique large multienzyme complex.
T. Lefebvre - One of the best experts on this subject based on the ideXlab platform.
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Gut-specific actinobacterial community structure and diversity associated with the wood-feeding termite species, Nasutitermes corniger (Motschulsky) described by nested PCR-DGGE analysis
Insectes Sociaux, 2009Co-Authors: T. Lefebvre, E. Miambi, Alejandro Pando, Madiop Diouf, Corinne Rouland-lefèvreAbstract:This comprehensive survey studied the actinobacterial community structure and putative representative members associated with the gut of the wood-feeding termite, Nasutitermes corniger (Motschulsky), using nested PCR-DGGE and 16S rDNA sequences analyses. The closest relatives of the actinobacteria inhabiting the gut of Nasutitermes corniger were in five families, regardless of the geographical origin of the termite colony: Propionibacteriaceae, Streptomycetaceae, Cellulomonodaceae, Corynebacteriaceae and Rubrobacteraceae . Feeding termites on beech wood did not result in substantial changes in the actinobacterial community structure as revealed by DGGE banding patterns. Most of the 16S rDNA sequences obtained after excision and sequencing of DGGE bands clustered with those previously retrieved in termite guts. These results confirm the presence of gut-specific actinobacteria. Except for the 16S rDNA sequences affiliated to Streptomycetaceae and Cellulomonodaceae , no sequence had more than 97% similarity with the closest isolated strains, indicating the presence of microorganisms that have not yet been cultivated. These results suggest that members of the Actinomycetales order account for the largest proportion of the Actinobacteria phylum inhabiting the gut of the termite N. corniger .
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Gut-specific actinobacterial community structure and diversity associated with the wood-feeding termite species, Nasutitermes corniger (Motschulsky) described by nested PCR-DGGE analysis
Insectes Sociaux, 2009Co-Authors: T. Lefebvre, E. Miambi, Alejandro Pando, Madiop Diouf, Corinne Rouland-lefèvreAbstract:This comprehensive survey studied the actinobacterial community structure and putative representative members associated with the gut of the wood-feeding termite, Nasutitermes corniger (Motschulsky), using nested PCR-DGGE and 16S rDNA sequences analyses. The closest relatives of the actinobacteria inhabiting the gut of Nasutitermes corniger were in five families, regardless of the geographical origin of the termite colony: Propionibacteriaceae, Streptomycetaceae, Cellulomonodaceae, Corynebacteriaceae and Rubrobacteraceae . Feeding termites on beech wood did not result in substantial changes in the actinobacterial community structure as revealed by DGGE banding patterns. Most of the 16S rDNA sequences obtained after excision and sequencing of DGGE bands clustered with those previously retrieved in termite guts. These results confirm the presence of gut-specific actinobacteria. Except for the 16S rDNA sequences affiliated to Streptomycetaceae and Cellulomonodaceae , no sequence had more than 97% similarity with the closest isolated strains, indicating the presence of microorganisms that have not yet been cultivated. These results suggest that members of the Actinomycetales order account for the largest proportion of the Actinobacteria phylum inhabiting the gut of the termite N. corniger .
Virginia Aragon - One of the best experts on this subject based on the ideXlab platform.
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Variations in association of nasal microbiota with virulent and non-virulent strains of Glaesserella (Haemophilus) parasuis in weaning piglets
Veterinary Research, 2020Co-Authors: Yasser S. Mahmmod, Florencia Correa-fiz, Virginia AragonAbstract:Glaesserella (formerly Haemophilus ) parasuis causes Glässer’s disease, which results in high economic loss in the swine industry. To understand the polymicrobial interactions of G. parasuis and the nasal microbiota, the statistical association patterns of nasal colonizing bacteria with virulent and non-virulent strains of G. parasuis were studied accounting for the farm management practices as potential risk factors for the occurrence of Glässer’s disease. The nasal microbiota from 51 weaned-piglets from four farms with Glässer’s disease and three farms with no respiratory diseases was previously characterized and included in this study. The presence of virulent and/or non-virulent G. parasuis strains in the nasal cavities was determined in order to establish the potential association with other members of the nasal microbiota. Multivariate logistic and linear regression models were performed among the various members of nasal microbiota and G. parasuis . The multi-site production system and disease presence in the farm were both significantly associated with the presence of G. parasuis virulent strains in the nose of the piglets. Differential bacterial associations were observed with virulent or non-virulent G. parasuis . Chitinophagaceae , Corynebacteriaceae and Corynebacterium were positively associated with the virulent G. parasuis strains, while Enterobacteriaceae, Peptostreptococcaceae , Clostridium XI, and Escherichia/Shigella were negatively associated with virulent G. parasuis . On the other hand, Flavobacteriaceae , Planobacterium , and Phascolarctobacterium were positively associated with the non-virulent G. parasuis strains, while Rikenellaceae , Enterococcaceae , Odoribacter , and Corynebacterium were negatively associated with non-virulent G. parasuis . In conclusion, the nasal microbiota communities showed variations in the association with the G. parasuis strains type.
