Desulfovibrio gabonensis sp. nov., a New Moderately Halophilic Sulfate-Reducing Bacterium Isolated from an Oil Pipeline

Abstract

Two moderately halophilic sulfate-reducing bacteria were isolated from an African oil pipeline and designated strains SEBR 3640 and SEBR 2840T (T = type strain). Both of these strains possessed traits that define the genus Desulfovibrio. The cells of both isolates were motile curved rods that had a single polar flagellum and contained desulfoviridin, and both isolates utilized lactate, pyruvate, malate, fumarate, succinate, and ethanol in the presence of sulfate. Sulfite, thiosulfate, and elemental sulfur were also used as electron acceptors in the presence of lactate. However, both strains tolerated higher concentrations of NaCl (up to 17%) than all other Desulfovibrio species except Desulfovibrio halophilus, which tolerated a similar level of NaCl. The results of a 16s rRNA gene sequence analysis also placed the designated type strain, strain SEBR 2840, in the genus Desulfovibrio but revealed that this organism was significantly different from D. halophilus and all other validly described Desulfovibrio species. On the basis of our results, we propose that strain SEBR 2840T is a member of a new species of the genus Desulfovibrio, Desulfovibrio gabonensis. The type strain of D. gabonensis is strain SEBR 2840 (= DSM 10636).The presence of sulfate-reducing bacteria (SRB) in oil field waters has been recognized for a long time, and the activities of these microorganisms are closely linked to the history of oil. In 1926, Bastin et al. (3) studied the SRB communities in oil fields. After this pioneering work, several microbiological studies showed that SRB communities were widely distributed in most of the oil fields investigated (1, 5, 19).In the course of a survey of different oil fields, we isolated several strains of SRB. Two strains, designated strains SEBR %40T (T = type strain) and SEBR 3640, were characterized further; these strains were isolated from water samples obtained from two oil pipelines transporting the oil produced at an offshore oil field to onshore facilities on the coast of Gabon (West Africa). Both strains were moderately halophilic, curved, rod-shaped organisms and on the basis of their morphological and physiological traits were assigned to the genus Desulfo-.vibrio. The results of a 16s rRNA gene sequence analysis of strain SEBR 2840T indicated that it was not related to any previously described Desulfovibrio species, and we propose that this strain should be assigned to a new species, Desulfovibrio gabonensis. Strain SEBR 2840 is the type strain of this species. MATERZALS AND METHODSSources of the isolates. Strain SEBR 2840T was isolated in February 1990 from a water sample taken from an oil pipeline linking offshore production platforms to onshore treatment facilities.Strain SEBR 3640 was isolated 1 year later from another pipeline in the same offshore oil field.Sampling and primary cultures of SRB were grown as described previously (4, 18). The total salinity of the culture media and the incubation temperature were

Marinobacter aquaeolei sp. nov., a halophilic bacterium isolated from a Vietnamese oil-producing well

“…have described halophilic bacteria obtained from such environments (Adkins et al, 1993;Dang et al, 1996;Tardy-Jacquenod et al, 1996a, b). In our microbial investigation of offshore oil/gas fields near the coastal town of Vung Tau in southern Vietnam, several novel micro-organisms have been isolated, including halophilic sulfate-reducing bacteria (Dang et al, 1996).…”

Desulfovibrio bastinii sp. nov. and Desulfovibrio gracilis sp. nov., moderately halophilic, sulfate-reducing bacteria isolated from deep subsurface oilfield water

“…The 16S rRNA genes of SRL4225 T and SRL6146 T were amplified and their sequences determined and analysed as previously described (Tardy-Jacquenod et al, 1996). A new sequence of the 16S rRNA gene of Desulfovibrio longus DSM 6739 T was determined, for the purpose of this work, by using the same procedure.…”

“…The results of FASTA analysis of the 1416-nt 16S rRNA gene sequence of strain SRL4225 T against sequences in GenBank, and the construction of a phylogenetic tree as previously described (Tardy-Jacquenod et al, 1996), revealed that strain SRL4225 T forms a distinct cluster with the undescribed Desulfovibrio species strain ASPO3 (93?6 % similarity, distance matrix value), Desulfovibrio hydrothermalis (92?6 %), Desulfovibrio salexigens (91?8 %) and Desulfovibrio zosterae (91?7 %) (Fig. 2).…”

“…The physiological and metabolic characterization of the strains included tests to determine utilization of different carbon substrates and energy sources, utilization of a variety of electron acceptors, fermentative growth, temperature, pH and salinity optima, vitamin requirements and pigment content; the tests used have been described previously (Magot et al, 1992;Tardy-Jacquenod et al, 1996).…”

Desulfovibrio putealis sp. nov., a novel sulfate-reducing bacterium isolated from a deep subsurface aquifer

“…To obtain a picture of the physiological properties of strain B7-43 T , the following tests were carried out: utilization of carbon and energy sources, utilization of a variety of electron acceptors, fermentative growth tests and determination of temperature, pH and salinity optima (Magot et al, 1992;Pfennig et al, 1981;Tardy-Jacquenod et al, 1996;Widdel & Bak, 1992). All tests were performed in triplicate.…”