Pelobacter seleniigenes sp. nov., a selenate-respiring bacterium

Abstract

Strain KMT is a novel bacterium with the unique metabolic abilities of being able to respire selenate as the electron acceptor using acetate as the carbon substrate and possessing the ability to grow fermentatively on short-chain organic acids such as lactate, citrate and pyruvate. Strain KMT was isolated from a sediment enrichment culture of a highly impacted wetland system in New Jersey, USA. Strain KMT is able to reduce selenate as well as selenite to elemental selenium. The unique metabolic capabilities of strain KMT include the respiration of nitrate, poorly crystalline Fe(III) and anthraquinone disulfonate. Phylogenetic analysis of the 16S rRNA gene of the novel isolate indicates that strain KMT groups within the family Geobacteraceae in the class Deltaproteobacteria with approximately 96–97 % 16S rRNA gene sequence similarity to the closest known organisms Malonomonas rubra Gra Mal 1T, Pelobacter acidigallici Ma Gal 2T and species of the genus Desulfuromusa. Recognized species of the genera Malonomonas and Pelobacter cannot use any inorganic electron acceptors, while strains of the genus Desulfuromusa do not ferment organic substrates. This contrasts with the ability of strain KMT to ferment organic compounds as well as to couple selenate reduction to acetate utilization. Based on 16S rRNA gene phylogeny and metabolic properties, strain KMT represents a novel species for which the name Pelobacter seleniigenes sp. nov. (type strain KMT=DSM 18267T=ATCC BAA-1388T) is proposed. Based on the phylogenetic grouping of species of the genus Pelobacter within the Desulfuromusa cluster, it is suggested that Malonomonas rubra Gra Mal 1T should also be included in this group.

Control of Sulfide Production in High Salinity Bakken Shale Oil Reservoirs by Halophilic Bacteria Reducing Nitrate to Nitrite

“…Community compositions of SW-IW samples were dominated by microorganisms, which grow optimally at moderate salinities (Table 2, Table S2) such as Methanolobus (optimum 0.35 M NaCl; Michimaru et al, 2009), Thiomicrospira (optimum 0.47 M NaCl; Brinkhoff and Kuever, 1999), Desulfovibrio (optimum 1.0 M NaCl for halophilic Desulfovibrio ; Tardy-Jacquenod et al, 1998), Methanobacterium (optimum 0.1 M NaCl with tolerance of up to 1.7 M NaCl for some strains; Cadillo-Quiroz et al, 2014) and Pelobacter (minimally 0.2 M NaCl; Nasaringarao and Häggblom, 2007). Of these members of the genus Desulfovibrio are SRB known to be involved in reservoir souring and microbially influenced corrosion (Hubert et al, 2009; Kakooei et al, 2012; Guan et al, 2014) at low salinity and low temperature conditions.…”

Selenium environmental cycling and bioavailability: a structural chemist point of view

“…Later, dissimilatory sulfate-independent bacterial respiration was discovered (Oremland et al 1989) (this sulfate-independent respiration has been recently proved by Lenz et al (2008b), who fed bacteria with sulfate in 2,600 molar excess to selenate in a continuous manner, showing that selenate still was completely reduced). Since then, many bacterial cultures capable of selenate and selenite respiratory growth have been observed (Basaglia et al 2007;Blum et al 1998;Ghosh et al 2008;Hunter 2007;Hunter et al 2007;Macy et al 1989;Narasingarao and Haggblom 2007; see review by Stolz et al 2006;Stolz and Oremland 1999). To date, about 16 diverse species of bacteria and archaea have been described that grow anaerobically by linking the oxidation of organic substrates or H 2 to the dissimilatory reduction of selenium oxyanions (Oremland and Stolz 2000;Stolz and Oremland 1999).…”

The Family Desulfuromonadaceae

“…NT not tested, PGCA phloroglucinol carboxylate, PEG polyethylene glycols a Schink and Pfennig (1982) b Schink (1985) c Schink (1984) d Schink and Stieb (1983) e Schnell et al (1991) f Narasingarao and Häggblom (2007) g Growth was possible in mixed culture with Acetobacterium woodii or Methanospirillum hungatei (Schink 1984;Schink 2006) h Growth was possible only in the presence of 10 mM acetate (Schink 1984;Schink 2006) Fatty acid content has been only reported for P. seleniigenes and is composed of predominantly the straight chain fatty acids of C 15:0 , C 16:0 and C 17:0 . Pelobacter are able to grow syntrophically in anoxic environments.…”