Desulfovibrio alcoholovorans sp. nov., a sulfate-reducing bacterium able to grow on glycerol, 1,2- and 1,3-propanediol

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Effects of sulfate on lactate and C2-, C3- volatile fatty acid anaerobic degradation by a mixed microbial culture

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Sulfate reduction and anaerobic glycerol degradation by a mixed microbial culture

39 ref.International audienc

Geochemical and microbial community determinants of reductive dechlorination at a site biostimulated with glycerol

Biostimulation is widely used to enhance reductive dechlorination of chlorinated ethenes in contaminated aquifers. However, the knowledge on corresponding biogeochemical responses is limited. In this study glycerol was injected in an aquifer contaminated with cis-dichloroethene (cDCE), and geochemical and microbial shifts were followed for 265 days. Consistent with anoxic conditions and sulfate reduction after biostimulation, MiSeq 16S rRNA gene sequencing revealed temporarily increased relative abundance of Firmicutes, Bacteriodetes and sulfate reducing Deltaproteobacteria. In line with 13C cDCE enrichment and increased Dehalococcoides mccartyi (Dcm) numbers, dechlorination was observed towards the end of the field experiment, albeit being incomplete with accumulation of vinyl chloride. This was concurrent with i) decreased concentrations of dissolved organic carbon (DOC), reduced relative abundances of fermenting and sulfate reducing bacteria that have been suggested to promote Dcm growth by providing electron donor (H2) and essential corrinoid cofactors, ii) increased sulfate concentration and increased relative abundance of Epsilonproteobacteria and Deferribacteres as putative oxidizers of reduced sulfur compounds. Strong correlations of DOC, relative abundance of fermenters and sulfate reducers, and dechlorination imply the importance of syntrophic interactions to sustain robust dechlorination. Tracking microbial and environmental parameters that promote/preclude enhanced reductive dechlorination should aid development of sustainable bioremediation strategies. This article is protected by copyright. All rights reserved.This study was supported by a VITO/KU Leuven PhD scholarship (EU FP7 project AQUAREHAB, grant 226565) to S Atashgahi. Furthermore, S Atashgahi and H Smidt received support bya grant ofBE-Basic-FES funds from theDutch Ministry of Economic Affairs and D Springael by the InterUniversity Attraction Pole (IUAP) “m-manager” of the Belgian Science Policy (BELSPO, P7/25). We thankRichard Lookman for his assistance in the field experiment and acknowledge the China Scholarship Council for the support to Y Lu and Y Zheng.info:eu-repo/semantics/publishedVersio

The deep-subsurface sulfate reducer Desulfotomaculum kuznetsovii employs two methanol-degrading pathways

Methanol is generally metabolized through a pathway initiated by a cobalamine-containing methanol methyltransferase by anaerobic methylotrophs (such as methanogens and acetogens), or through oxidation to formaldehyde using a methanol dehydrogenase by aerobes. Methanol is an important substrate in deep-subsurface environments, where thermophilic sulfate-reducing bacteria of the genus Desulfotomaculum have key roles. Here, we study the methanol metabolism of Desulfotomaculum kuznetsovii strain 17T, isolated from a 3000-m deep geothermal water reservoir. We use proteomics to analyze cells grown with methanol and sulfate in the presence and absence of cobalt and vitamin B12. The results indicate the presence of two methanol-degrading pathways in D. kuznetsovii, a cobalt-dependent methanol methyltransferase and a cobalt-independent methanol dehydrogenase, which is further confirmed by stable isotope fractionation. This is the first report of a microorganism utilizing two distinct methanol conversion pathways. We hypothesize that this gives D. kuznetsovii a competitive advantage in its natural environment.Research was funded by grants of the Division of Chemical Sciences (CW-TOP 700.55.343) and Earth and Life Sciences (ALW 819.02.014) of The Netherlands Organisation for Scientific Research (NWO), the European Research Council (ERC grant 323009), and the Gravitation grant (024.002.002) of the Netherlands Ministry of Education, Culture and Scienceinfo:eu-repo/semantics/publishedVersio

Efecto de la inmovilización celular sobre el tratamiento del alpechín con una bacteria que degrada polifenoles y los ácidos acéticos y fórmico

Olive mill wastewater (OMW) is a pure vegetative by-product, containing a high organic and polyphenol content and is resistant to biodegradation. Its disposal lead to major environmental pollution problems in the Mediterranean basin. An aerobic bacterium was isolated from OMW. During three consecutive diluted and supplemented OMW treatment cycles, significant abatement of its phytotoxic substances was observed. In fact, total phenols, acetic and formic acids were reduced between 33 and 64 % when cells of the isolated bacterium were grown free; and between 62 and 78 % when cells of the same isolated bacterium were grown immobilized in a polyurethane sponge. These results suggest that the bacterium culture of the new isolate would decrease the OMW phytotoxicity. Phylogenetic analysis of 16S ribosomal DNA showed that all the related sequences are members of the Enterobacteriaceae family and revealed that the isolated bacterium was characterized as a Klebsiella oxytoca strain.El alpechín (OMW) es un residuo puro de la extracción del aceite de oliva, que contiene una elevada carga orgánica y de polifenoles por lo que es resistente a la degradación. Su descarga produce graves problemas de contaminación medioambiental en toda el área mediterránea. Se ha aislado una bacteria anaerobia del OMW, que , durante tres ciclos consecutivos de tratamiento del OMW diluido y suplementado, produjo una disminución significativa de las sustancias fitotóxicas del residuo. De hecho, la concentración en fenoles totales, ácido acético y ácido fórmico se redujeron entre 33 y 64 % cuando las células no estaban inmovilizadas y entre el 62 y 78 % cuando las células bacterianas se inmovilizaron en una esponja de poliuretano. Estos resultados indican que el cultivo de la nueva bacteria aislada puede disminuir la fototoxicidad del alpechín. Análisis filogenético del ribosoma 16S de DNA demostró que todas las secuencias eran miembros de la familia Enterobacteriaceae y que la bacteria aislada podía identificarse como una cepa de Klebsiella oxytoca

Fermentation du D lactate, du glycerol et des diols par les bacteries sulfato-reductrices du genre Desulfovibrio

SIGLEINIST T 80210 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Glycerol fermentation and sulfate utilization during the anaerobic digestion process

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