Desulfobulbus oligotrophicus sp. nov., a sulfate-reducing and propionate-oxidizing bacterium isolated from a municipal anaerobic sewage sludge digester

Abstract

A novel, mesophilic, strictly anaerobic, sulfate-reducing and propionate-oxidizing bacterium, strain Prop6T, was enriched and isolated from a municipal anaerobic sewage sludge digester. Cells were Gram-stain-negative, catalase-positive, oval rods, motile by means of amphitrichous flagella, non-spore-forming and contained menaquinone MK-5(H2) as the major respiratory quinone. The genomic DNA G+C content was 51.7 mol%. The optimal NaCl concentration, temperature and pH were 2-5 g l-1, 35 °C and pH 7.6, respectively. Strain Prop6T could only oxidize propionate, lactate and pyruvate (weakly) with sulfate, sulfite or thiosulfate, mainly to acetate. Strain Prop6T fermented pyruvate and lactate to acetate and propionate. The predominant cellular fatty acids were C14 : 0, C16 : 0, C16 : 1ω7, C16 : 1ω5, C17 : 1ω6 and C18 : 1ω7. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the newly isolated strain was a member of the genus Desulfobulbus, with Desulfobulbus elongatus DSM 2908T, Desulfobulbus propionicus DSM 2032T and Desulfobulbus rhabdoformis DSM 8777T as closest relatives among species with validly published names. On the basis of genotypic, phenotypic and chemotaxonomic characteristics, it is proposed that the isolate represents a novel species, Desulfobulbus oligotrophicus sp. nov. The type strain is Prop6T (=DSM 103420T=JCM 31535T).

Insights into the Evolution of Host Association through the Isolation and Characterization of a Novel Human Periodontal Pathobiont,Desulfobulbus oralis

“…As with other oral species, it has remained unclear if those organisms play a role in the etiology of periodontitis or their increased abundance is a consequence of the disease state, with deep subgingival pockets favoring the proliferation of strict anaerobes. No host-associated species of Desulfobulbus has been cultivated so far, although multiple free-living relatives have been isolated and characterized from aquatic and sediment samples (23)(24)(25)(26)(27)(28)(29). All free-living Desulfobulbus species are sulfate reducers, strict anaerobes, largely prototrophic, and use a variety of electron donors and acceptors.…”

Influence of the artificial sodium saccharin sweetener Sucram®on the microbial community composition in the rumen content and attached to the rumen epithelium in dairy cattle: A pilot study

“…Two OTUs (6 and 34) with reduced abundance found in samples supplemented with Sucram ® were classified as potential sulfate-reducing bacteria (SRB) within the Desulfobulbus genus and were related to Desulfobulbus oligotrophicus (sequence similarity >97% using NCBI BLAST [46, 47]. SRB are commonly found within the gastrointestinal tract of ruminants [48] and particularly at the rumen wall [44, 49] and are known to reduce SO 3 2− to SO 4 2− and H 2 S [50].…”

Sulfate Alters the Competition Among Microbiome Members of Sediments Chronically Exposed to Asphalt

“…Indeed, the main SRMs present in the asphalt-exposed microcosms already on day 0, were part of the highly versatile Desulfobulbus genus. Representative species of Desulfobulbus are capable of both respiratory and fermentative growth ( Laanbroek et al, 1982 ; Sass et al, 2002 ; El Houari et al, 2017 ; Kharrat et al, 2017 ) and are considered generalists, based on their metabolic flexibility. Lineages within the Desulfobulbaceae family have been previously identified as carriers of genes coding for monoaromatic degrading enzymes ( von Netzer et al, 2016 ), although the high share of Desulfobulbus did not result in an increased potential for degradation of monoaromatics as inferred via bamA gene abundance in our experiment.…”