Bernard Ollivier

Aix-Marseille Université, Marsiglia, Provence-Alpes-Côte d'Azur, France

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Publications (236)

  • Article · Sep 2016 · International Journal of Systematic and Evolutionary Microbiology
  • [Show abstract] [Hide abstract] ABSTRACT: A mesophilic anaerobic bacterium, designated KHALHBD91T was isolated from the moderately hot spring of Hamman Biadha, Tunisia. The strain was Gram staining negative, non sporulating, non motile and rod shaped, appearing singly (0.5-2.0µm x 0.5-1µm).It grew anaerobically at temperatures between 20 and 50°C (optimum 37°C) and at pH between 5.5-7.8 (optimum 7.0). It required NaCl for growth, and with growth observed to 8.5% and an optimum at 2.5%. Strain KHALHBD91T used glucose, galactose, maltose, pyruvate, lactate, fumarate, yeast extract as electron donors. The end-products from glucose fermentation were acetate, propionate, succinate and CO2. Nitrate, nitrite, thiosulfate, elemental sulfur, sulfate, and sulfite were not used as terminal electron acceptors. The predominant cellular fatty acids were anteiso-C15:0 and iso-C15:0. Respiratory quinone was MK-6. The main polar lipids consisted of lipids, phospholipids, glycolipids, aminolipids, phosphoaminoglycolipids and phosphatidylethanolamine. The DNA G+C content was 35.0 mol %.Phylogenetic analysis of the small-subunit ribosomal 16S rRNA gene sequence indicated that strain KHALHBD91T had Marinifilum fragile and Marinifilum flexuosum (phylum "Bacteroidetes", class Bacteroidia, order Bacteroidales) as its closest relatives (similarity of 86.7 % and 87.8% respectively). The phylogenetic and physiological data of the present study strongly suggest that the isolate represents a novel genus and species of a novel family, Balneicella halophila gen. nov., sp. nov., in the family Balneicellaceae fam. nov. The type strain is KHALHBD91T (= DSM =28579T = JCM= 19909T).
    Article · Sep 2016 · International Journal of Systematic and Evolutionary Microbiology
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    File available · Dataset · Aug 2016
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    File available · Dataset · Aug 2016
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    File available · Dataset · Aug 2016
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    [Show abstract] [Hide abstract] ABSTRACT: A novel anaerobic, alkaliphilic, Gram-positive, spore-forming bacterium was isolated from a carbonaceous hydrothermal chimney in the Prony Bay, New Caledonia. This bacterium designated strain 3bT grew at temperatures from 30 to 43 °C (optimum 37°C) and at pH between 7.8 and 10.1 (optimum 9.5). Added NaCl was not required for growth (optimum 0-0.2%), but was tolerated up to 4%. Yeast extract was required for growth. Strain 3bT utilized crotonate, lactate, and pyruvate, but not sugars. Crotonate was dismutated to acetate and butyrate. Lactate was disproportionated to acetate and propionate. Pyruvate was degraded to acetate, and traces of hydrogen. Growth on lactate was improved by addition of fumarate, which was used as electron acceptor and converted into succinate. Sulfate, thiosulfate, elemental sulfur, sulfite, nitrate, nitrite, FeCl3, FeIII-citrate, FeIII-EDTA, chromate, arsenate, selenate, and DMSO were not used as terminal electron acceptors. The G+C content of the genomic DNA was 33.2 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that the isolate is a member of the family Clostridiaceae, order Clostridiales within the phylum Firmicutes. Strain 3bT was most closely related to Alkaliphilus hydrothermalis FatMR1T (92.2% 16S rRNA gene sequence identity), and was positioned approximately equidistantly between the genera Alkaliphilus, Anaerovirgula, and Natronincola. On the basis of phylogenetic, genetic, chimiotaxonomic, and physiological properties, strain 3bT is proposed to represent the first species of a novel genus, for which the name Serpentinicella alkaliphila gen. nov., sp. nov. is proposed (type strain 3bT = DSM 100013T = JCM 30645T).
    Full-text available · Article · Aug 2016 · International Journal of Systematic and Evolutionary Microbiology
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    [Show abstract] [Hide abstract] ABSTRACT: Two novel strictly anaerobic bacteria, strains Bs105T and Bs107T, were isolated from a deep aquifer-derived hydrocarbonoclastic community. The cells were rod-shaped, not motile and had terminal spores. Phylogenetic affiliation and physiological properties revealed that these isolates belong to two new species of the genus Desulfotomaculum. Optimal growth temperatures for strain Bs105T and Bs107T were 42°C and 45°C, respectively. The estimated G+C content of the genomic DNA was 42.9% and 48.7%. For both strains, the major cellular fatty acid was palmitate (C16:0). Specific carbon fatty acid signatures of Gram-positive bacteria (iso-C17:0) and sulfate-reducing bacteria (C17:0cyc) were also detected. An insertion was revealed in one of the two 16S rRNA gene copies harbored by strain Bs107T. Similar insertions were already highlighted among moderately thermophilic Desulfotomaculum species. Both strains shared the ability to oxidize aromatic acids (Bs105T: hydroquinone, acetophenone, para-toluic acid, 2-phenylethanol, trans-cinnamic acid, 4-hydroxybenzaldehyde, benzyl alcohol, benzoic acid 4-hydroxybutyl ester; Bs107T: ortho-toluic acid, benzoic acid 4-hydroxybutyl ester). The names Desulfotomaculum aquiferis sp. nov. and Desulfotomaculum profundi sp. nov. are proposed for the type strains Bs105T (=DSM 24088T = JCM 31386T) and Bs107T (= DSM 24093T = JCM 31387T).
    Full-text available · Article · Jul 2016 · International Journal of Systematic and Evolutionary Microbiology
  • [Show abstract] [Hide abstract] ABSTRACT: Desulfovibrio piezophilus strain C1TLV30(T) is a mesophilic piezophilic sulfate-reducer isolated from Wood Falls at 1700 m depth in the Mediterranean Sea. In this study, we analysed the effect of the hydrostatic pressure on this deep-sea living bacterium at the physiologic and transcriptomic levels. Our results showed that lactate oxidation and energy metabolism were affected by the hydrostatic pressure. Especially, acetyl-CoA oxidation pathway and energy conservation through hydrogen and formate recycling would be more important when the hydrostatic pressure is above (26 MPa) than below (0.1 MPa) the optimal one (10 MPa). This work underlines also the role of the amino acid glutamate as a piezolyte for the Desulfovibrio genus. The transcriptomic analysis revealed 146 differentially expressed genes emphasizing energy production and conversion, amino acid transport and metabolism and cell motility and signal transduction mechanisms as hydrostatic pressure responding processes. This dataset allowed us to identify a sequence motif upstream of a subset of differentially expressed genes as putative pressure-dependent regulatory element.
    Article · Jun 2016 · Environmental Microbiology Reports
  • Poster · May 2016
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    [Show abstract] [Hide abstract] ABSTRACT: Microbiology of a hypersaline oil reservoir located in Central Africa was investigated with molecular and culture methods applied to preserved core samples. Here we show that the community structure was partially acquired during sedimentation, as many prokaryotic 16S rRNA gene sequences retrieved from the extracted DNA are phylogenetically related to actual Archaea inhabiting surface evaporitic environments, similar to the Cretaceous sediment paleoenvironment. Results are discussed in term of microorganisms and/or DNA preservation in such hypersaline and Mg-rich solutions. High salt concentrations together with anaerobic conditions could have preserved microbial/molecular diversity originating from the ancient sediment basin wherein organic matter was deposited.
    Full-text available · Article · Mar 2016 · Scientific Reports
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    [Show abstract] [Hide abstract] ABSTRACT: The current paper reports on the purification of an extracellular thermostable keratinase (KERCA) produced from C. algeriensis strain TH7C1T, a thermophilic, anaerobic bacterium isolated from a hydrothermal hot spring in Algeria. The maximum keratinase activity recorded after 24-h of incubation at 50 °C was 21000 U/ml. The enzyme was purified by ammonium sulfate precipitation-dialysis and heat treatment (2 h at 50 °C) followed by UNO Q-6 FPLC anion exchange chromatography, and submitted to biochemical characterization assays. Matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/MS) analysis revealed that the purified enzyme was a monomer with a molecular mass of 33246.10 Da. The sequence of the 23 N-terminal residues of KERCA showed high homology with those of bacterial keratinases. Optimal activity was achieved at pH 7 and 50 °C. The enzyme was completely inhibited by phenylmethanesulfonyl fluoride (PMSF) and diiodopropyl fluorophosphates (DFP), which suggests that it belongs to the serine keratinase family. KERCA displayed higher levels of hydrolysis and catalytic efficiency than keratinase KERQ7 from Bacillus tequilensis strain Q7. These properties make KERCA a potential promising and eco-friendly alternative to the conventional chemicals used for the dehairing of goat, sheep, and bovine hides in the leather processing industry.
    Full-text available · Article · Jan 2016 · International journal of biological macromolecules
  • [Show abstract] [Hide abstract] ABSTRACT: Taking into account their 16S rRNA gene sequences, it appears that Acetomicrobium flavidum and the three Anaerobaculum species described so far belong to the same phylogenetic clade with high levels (>95 %) of similarity. In this respect, these three Anaerobaculum species should be reclassified within the genus Acetomicrobium which has priority over the genus Anaerobaculum since being validated later after the genus Acetomicrobium. The DNA G+C content of A. flavidum is 47.1 mol %, which is in the same order as that of the three Anaerobaculum species. All these bacteria have in common iso-C15:0 as their main fatty acid. Based on further phylogenetic, genetic, and chemotaxonomic studies, we propose Anaerobaculum mobile (= DSM 13181T = JCM 12221T), Anaerobaculum thermoterrenum (=DSM 13490T = ACM 5076T) and Anaerobaculum hydrogeniformans (= DSM 22491T =ATCC BAA-1850T) to be reclassified as Acetomicrobium mobile comb. nov., Acetomicrobium thermoterrenum comb. nov. and Acetomicrobium hydrogeniformans comb. nov., respectively. The four bacterial species belong to the phylum Synergistetes.
    Article · Jan 2016 · International Journal of Systematic and Evolutionary Microbiology
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    [Show abstract] [Hide abstract] ABSTRACT: The present study investigates the purification and biochemical characterization of an extracellular thermostable xylanase (called XYN35) from Caldicoprobacter algeriensis sp. nov., strain TH7C1T, a thermophilic, anaerobic strain isolated from the hydrothermal hot spring of Guelma (Algeria). The maximum xylanase activity recorded after 24 h of incubation at 70 °C and in an optimized medium containing 10 g/l mix birchwood- and oats spelt-xylan, was 250 U/ml. The pure protein was obtained after heat treatment (1 h at 70 °C), followed by sequential column chromatographies on Sephacryl S-200 gel filtration and Mono-S Sepharose anion-exchange. Matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/MS) analysis indicated that the purified enzyme is a monomer with a molecular mass of 35,075.10 Da. The results from amino-acid sequence analysis revealed high homology between the 21 NH2-terminal residues of XYN35 and those of bacterial xylanases. The enzyme showed optimum activity at pH 11 and 70 °C. While XYN35 was activated by Ca2+, Mn2+, and Mg2+, it was completely inhibited by Hg2+ and Cd2+. The xylanase showed higher specific activity on soluble oat-spelt xylan, followed by beechwood xylan. This enzyme was also noted to obey the Michaelis-Menten kinetics, with Km and kcat values on oat-spelt xylan being 1.33 mg/ml and 400 min-1, respectively. Thin-layer chromatography soluble oat-spelt xylan (TLC) analysis showed that the final hydrolyzed products of the enzyme from birchwood xylan were xylose, xylobiose, and xylotriose. Taken together, the results indicated that the XYN35 enzyme has a number of attractive biochemical properties that make it a potential promising candidate for future application in the pulp bleaching industry.
    Full-text available · Article · Dec 2015 · Carbohydrate Research
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    File available · Dataset · Sep 2015
  • Nathalie Pradel · Maxime Fuduche · Bernard Ollivier
    [Show abstract] [Hide abstract] ABSTRACT: In this study, we report for the first time the presence of magnetotactic bacteria (MTB) on the Northeastern Atlantic coast. Microscopy observations indicated a heterogeneous population of MTB morphotypes. The analysis of the 16S rDNA by pyrosequencing technology revealed four operational taxonomic sequence units affiliated within the Magnetococcales order, class Alphaproteobacteria. One of them was closely related to sequences of MTB from the Tunisian coast, central Mediterranean Sea. This work offers information on anew environmental context and on biogeography of MTB, highlights the putative impact that marine currents may have on MTB distribution on Earth, and underlines the role that pristine or polluted areas may play on the structure of the MTB communites.
    Article · Sep 2015 · Environmental Science and Pollution Research
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    [Show abstract] [Hide abstract] ABSTRACT: Active carbonate chimneys from the shallow marine serpentinizing Prony Hydrothermal Field were sampled 3 times over a 6 years period at site ST09. Archaeal and bacterial communities composition was investigated using PCR-based methods (clone libraries, Denaturating Gel Gradient Electrophoresis, quantitative PCR) targeting 16S rRNA genes, methyl coenzyme M reductase A and dissimilatory sulfite reductase subunit B genes. Methanosarcinales (Euryarchaeota) and Thaumarchaea were the main archaeal members. The Methanosarcinales, also observed by epifluorescent microscopy and FISH, consisted of two phylotypes that were previously solely detected in two other serpentinitzing ecosystems (The Cedars and Lost City Hydrothermal Field). Surprisingly, members of the hyperthermophilic order Thermococcales were also found which may indicate the presence of a hot subsurface biosphere. The bacterial community mainly consisted of Firmicutes, Chloroflexi, Alpha-, Gamma-, Beta-, and Delta-proteobacteria and of the candidate division NPL-UPA2. Members of these taxa were consistently found each year and may therefore represent a stable core of the indigenous bacterial community of the PHF chimneys. Firmicutes isolates representing new bacterial taxa were obtained by cultivation under anaerobic conditions. Our study revealed diverse microbial communities in PHF ST09 related to methane and sulfur compounds that share common populations with other terrestrial or submarine serpentinizing ecosystems.
    Full-text available · Article · Sep 2015 · Frontiers in Microbiology
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    File available · Dataset · Aug 2015
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    [Show abstract] [Hide abstract] ABSTRACT: Caldicoprobacter guelmensis isolated from the hydrothermal hot spring of Guelma (Algeria) produced high amounts of extracellular thermostable serine alkaline protease (called SAPCG) (23,000 U/mL). The latter was purified by ammonium sulphate precipitation, UNO Q-6 FPLC and Zorbex PSM 300 HPLC, and submitted to biochemical characterization assays. Matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/MS) analysis revealed that the purified enzyme was a monomer, with a molecular mass of 55824.19Da. The 19 N-terminal residue sequence of SAPCG showed high homology with those of microbial proteases. The enzyme was completely inhibited by phenylmethanesulfonyl fluoride (PMSF) and diiodopropyl fluorophosphates (DFP), which suggested its belonging to the serine protease family. It showed optimum protease activity at pH 10 and 70°C with casein as a substrate. The thermoactivity and thermostability of SAPCG were enhanced in the presence of 2mM Ca(2+). Its half-life times at 80 and 90°C were 180 and 60min, respectively. Interestingly, the SAPCG protease exhibited significant compatibility with iSiS and Persil, and wash performance analysis revealed that it could remove blood-stains effectively. Overall, SAPCG displayed a number of attractive properties that make it a promising candidate for future applications as an additive in detergent formulations. Copyright © 2015. Published by Elsevier B.V.
    Full-text available · Article · Aug 2015 · International journal of biological macromolecules
  • [Show abstract] [Hide abstract] ABSTRACT: Lab-scale 2L-anaerobic sequencing batch reactor was operated under mesothermic conditions. The degradation of protein-rich organic matter was determined by chemical oxygen demand, biogas production, and protein-removal activity over the operation. The structure of the microbial community was determined by qPCR and next-generation sequencing on 16S rRNA genes. At the steady state, a very efficient removal of protein (92 %) was observed. Our results demonstrate a decrease of archaeal and bacterial abundance over time. Members of the phylum Synergistetes, with a peculiar emphasis for those pertaining to families Dethiosulfovibrionaceae and Aminiphilaceae, are of major ecological significance regarding the treatment of this industrial wastewater. The prominent role to be played by members of the phylum Synergistetes regarding protein and/or amino acid degradation is discussed.
    Article · Jul 2015 · Environmental Science and Pollution Research
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    [Show abstract] [Hide abstract] ABSTRACT: Strain KhalAKB1T, a novel mesophilic, anaerobic rod-shaped bacterium was isolated from waters collected from a mesothermic tunisian spring. Cells are Gram-positive staining rods, occurring singly or in pairs and motile by one lateral flagellum. Strain KhalAKB1T grows at temperatures between 15° C and 45° C (optimum 30°C), pH between 5.5 and 8.5 (optimum 7.0) and NaCl concentration between 0 and 35 g l-1 (optimum 1 g l-1). It ferments yeast extract and a wide range of carbohydrates as electron donors including cellobiose, D-glucose, D-ribose, D-sucrose, D-xylose, D-maltose, D-galactose, and starch. Acetate, ethanol, CO2, and H2, are end products from glucose metabolism. It reduces elemental sulfur, but not sulfate, thiosulfate or sulfite, into sulfide The DNA G+C content is 37.6 mol %. The predominant cellular fatty acids are C14:0 and C16:0. Phylogenetic analysis of the 16S rRNA gene sequence suggests Fusibacter bizertensis as being the closest relative of this isolate (identity of 97.2 %). Based on phenotypic, phylogenetic and genotypic taxonomic characteristics, strain KhalAKB1T is proposed to be assigned to a novel species within the genus Fusibacter, order Clostridiales, Fusibacter fontis sp. nov. The type strain is KhalAKB1T (= DSM 28450 = JCM 19912).
    Full-text available · Article · Jul 2015 · International Journal of Systematic and Evolutionary Microbiology

Publication Stats

5k Citations


  • 1986-2014
    • Aix-Marseille Université
      • Département de biologie
      Marsiglia, Provence-Alpes-Côte d'Azur, France
    • University of California, Los Angeles
      Los Ángeles, California, United States
  • 2004-2006
    • Institute of Research for Development
      Marsiglia, Provence-Alpes-Côte d'Azur, France
  • 1996-2003
    • Griffith University
      Southport, Queensland, Australia