title: Reconstructing metabolic pathways of a member of the genus Pelotomaculum suggesting its potential to oxidize benzene to carbon dioxide with direct reduction of sulfate.
abstract: The enrichment culture BPL is able to degrade benzene with sulfate as electron acceptor and is dominated by an organism of the genus Pelotomaculum. Members of Pelotomaculum are usually known to be fermenters, undergoing syntrophy with anaerobic respiring microorganisms or methanogens. By using a metagenomic approach, we reconstructed a high-quality genome (∼2.97 Mbp, 99% completeness) for Pelotomaculum candidate BPL. The proteogenomic data suggested that (1) anaerobic benzene degradation was activated by a yet unknown mechanism for conversion of benzene to benzoyl-CoA; (2) the central benzoyl-CoA degradation pathway involved reductive dearomatization by a class II benzoyl-CoA reductase followed by hydrolytic ring cleavage and modified β-oxidation; (3) the oxidative acetyl-CoA pathway was utilized for complete oxidation to CO2. Interestingly, the genome of Pelotomaculum candidate BPL has all the genes for a complete sulfate reduction pathway including a similar electron transfer mechanism for dissimilatory sulfate reduction as in other Gram-positive sulfate-reducing bacteria. The proteome analysis revealed that the essential enzymes for sulfate reduction were all formed during growth with benzene. Thus, our data indicated that, besides its potential to anaerobically degrade benzene, Pelotomaculum candidate BPL is the first member of the genus that can perform sulfate reduction.
authors.affiliation: Biofilm Centre, University of Duisburg-Essen, Universitätsstrasse 5, 45141 Essen, Germany.|Helmholtz Zentrum München, Institute of Groundwater Ecology, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany.
authors.forename: Xiyang
authors.initials: X
authors.lastname: Dong
authors.affiliation: Helmholtz Centre for Infection Research, Computational Biology of Infection Research, 38124, Braunschweig, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Dröge
authors.affiliation: Helmholtz Zentrum München, Research Unit Protein Science, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany.
authors.forename: Christine
authors.initials: C
authors.lastname: von Toerne
authors.affiliation: Helmholtz Zentrum München, Institute of Groundwater Ecology, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany.
authors.forename: Sviatlana
authors.initials: S
authors.lastname: Marozava
authors.affiliation: Helmholtz Centre for Infection Research, Computational Biology of Infection Research, 38124, Braunschweig, Germany.
authors.forename: Alice C
authors.initials: AC
authors.lastname: McHardy
authors.affiliation: Biofilm Centre, University of Duisburg-Essen, Universitätsstrasse 5, 45141 Essen, Germany.
authors.forename: Rainer U
authors.initials: RU
authors.lastname: Meckenstock
mesh_terms: D000214:Acyl Coenzyme A / Q000378:metabolism; D000693:Anaerobiosis; D001554:Benzene / Q000378:metabolism*; D002245:Carbon Dioxide / Q000378:metabolism*; D053858:Metabolic Networks and Pathways; D010084:Oxidation-Reduction; D044925:Oxidoreductases Acting on CH-CH Group Donors; D010459:Peptococcaceae / Q000378:metabolism*; D020543:Proteome / Q000378:metabolism; D013431:Sulfates / Q000378:metabolism*
chemical_list: D000214:Acyl Coenzyme A; D020543:Proteome; D013431:Sulfates; D002245:Carbon Dioxide; C037817:benzoyl-coenzyme A; D044925:Oxidoreductases Acting on CH-CH Group Donors; C109030:benzoyl-coenzyme A reductase (dearomatizing); D001554:Benzene
keywords: Pelotomaculum; anaerobic degradation; benzene; genome; proteome; sulfate reduction