Desulfovibrio mexicanus sp. nov., a Sulfate-reducing Bacterium Isolated from an Upflow Anaerobic Sludge Blanket (UASB) Reactor Treating Cheese Wastewaters

• Published in: Anaerobe 2000-10, Vol.6 (5), p.305-312
• Main Authors: Hernandez-Eugenio, Guadalupe, Fardeau, Marie-Laure, Patel, Bharat K.C., Macarie, Hervé, Garcia, Jean-Louis, Ollivier, Bernard
• Format: Article
• Language: English
• Subjects: Sulfate-reducing bacteria, cheese factory wastewater, UASB digester, thiosulfate disproportionation, Desulfovibrio mexicanus, phylogeny
• ISSN: 1075-9964; 1095-8274
• DOI: 10.1006/anae.2000.0354

A mesophilic sulfate-reducing bacterium, designated strain Lup1T(T=type strain) was isolated from a Mexican UASB digester treating cheese factory wastewater. The non-motile, Gram-negative, curved and non-spore-forming cells (1.7–2.5×0.5 μm) existed singly or in chains. Optimum growth occurred at 37°C and pH 7.2 in a medium containing lactate and thiosulfate. Strain Lup1Tused pyruvate, formate, Casamino acids, serine, cysteine, H2and ethanol as electron donors in the presence of thiosulfate as an electron acceptor and fermented pyruvate, Casamino acids, cysteine, and serine. Sulfate, elemental sulfur, and sulfite also served as electron acceptors but not nitrate or fumarate. Thiosulfate was disproportionated to sulfate and sulfide. The G+C content of the DNA was 66 mol%. Phylogenetic analysis based on 16S rDNA revealed that strain Strain Lup1Twas a member of the genus Desulfovibrio withDesulfovibrio aminophilus being the closest relative (similarity value of 91%). As strain Lup1Tis physiologically and phylogenetically different from other Desulfovibrio species, it is designated Desulfovibrio mexicanus sp. nov. (=DSM 13116).