Petrimonas sulfuriphila gen. nov., sp. nov., a mesophilic fermentative bacterium isolated from a biodegraded oil reservoir

Abstract

A mesophilic, anaerobic, fermentative bacterium, strain BN3T, was isolated from a producing well of a biodegraded oil reservoir in Canada. Cells were Gram-negative, non-motile rods that did not form spores. The temperature range for growth was 15–40 °C, with optimum growth at 37–40 °C. The strain grew with up 4 % NaCl, with optimum growth in the absence of NaCl. Tryptone was required for growth. Yeast extract and elemental sulfur stimulated growth. Growth was also enhanced during fermentation of glucose, arabinose, galactose, maltose, mannose, rhamnose, lactose, ribose, fructose, sucrose, cellobiose, lactate, mannitol and glycerol. Acetate, hydrogen and CO2were produced during glucose fermentation. Elemental sulfur and nitrate were used as electron acceptors and were reduced to sulfide and ammonium, respectively. The G+C content of the genomic DNA was 40·8 mol%. Phylogenetic analyses of the 16S rRNA gene sequence indicated that the strain was a member of the phylum ‘Bacteroidetes’, distantly related to the generaBacteroidesandTannerella(similarity values of less than 90 %). The chemotaxonomic data (fatty acids, polar lipids and quinones composition) also indicated that strain BN3Tcould be clearly distinguished from its closest cultivated relatives. This novel organism possesses phenotypic, chemotaxonomic and phylogenetic traits that do not allow its classification as a member of any previously described genus; therefore, it is proposed that this isolate should be described as a member of a novel species of a new genus,Petrimonasgen. nov., of whichPetrimonas sulfuriphilasp. nov. is the type species. The type strain is BN3T(=DSM 16547T=JCM 12565T).