Dethiosulfovibrio peptidovorans gen. nov., sp. nov., a New Anaerobic, Slightly Halophilic, Thiosulfate-Reducing Bacterium from Corroding Offshore Oil Wells

Abstract

A strictly anaerobic thiosulfate-reducing bacterium was isolated from a corroding offshore oil well in Congo and was designated strain SEBR 4207T. Pure culture of the strain induced a very active pitting corrosion of mild steel, with penetration rates of up to 4 mm per year. This constitutes the first experimental evidence of the involvement of thiosulfate reduction in microbial corrosion of steel. Strain SEBR 4207T cells were vibrios (3 to 5 by 1 pm), stained gram negative, and possessed lateral flagella. Spores were not detected. Optimum growth occurred in the presence of 3% NaCl at pH 7.0 and 42°C. Strain SEBR 4207T utilized peptides and amino acids, but not sugars or fatty acids. It fermented serine, histidine, and Casamino Acids, whereas arginine, glutamate, leucine, isoleucine, alanine, valine, methionine, and asparagine were only used in the presence of thiosulfate. Peptides were fermented to acetate, isobutyrate, isovalerate, 2-methylbutyrate, H,, and CO,. The addition of either thiosulfate or sulfur but not sulfate increased peptide utilization, growth rate, and biomass; during growth, H,S was produced and a concomitant decrease in H, was observed. The addition of either thiosulfate or sulfur also reversed H, inhibition. 16s rRNA sequence analysis indicates that strain SEBR 4207T is distantly related to members of the genus Thermoanuerobacter (83% similarity). Because the phenotypic and phylogenetic characteristics cannot be assigned to any described genus, strain SEBR 4207T is designated as a new species of a new genus, Dethiosulfovibrio peptidovorans gen. nov., sp. nov. Strain SEBR 4207T has been deposited in the Deutsche Sammlung von Mikroorganismen und zellkulturen GmbH (= DSM 11002).In 1989, Elf Congo experienced corrosion of the first 5 km of a 23-km main subsea pipeline that transported sour oil (i.e., H,S-containing petroleum) produced from the Emeraude oil field. The corroded segment was replaced, but it corroded again a year later. The whole line was then replaced and operated under a specifically designed biocide treatment regimen. The preliminary examination of the corroded iron showed that the breakthrough was due to bacterial pitting corrosion, with an unusually high penetration rate of about 1 cm per year. Chemical analysis of the pipeline water revealed the presence of up to 0.5 mM thiosulfate. It is likely that the thiosulfate was produced as a result of oxidation of the H,S naturally present in the oil field ecosystem by oxygen that is introduced in the pipelines during processing (10, 15, 22). The corrosion of pipelines was suspected to be due not only to sulfate but also to thiosulfate reduction by sulfate-reducing bacteria (SRB), because computer modeling had shown that thiosulfate reduction could induce the pitting corrosion of steel at higher rates than sulfate reduction (13).Since the pipeline was under a biocide treatment regimen during our microbiological investigations, the production fluids from several wellheads upstream of the line were collected and analyzed. Besides diffe...

Rôle des bactéries sulfurogènes dans la corrosion du fer

“…Elf mentionne qu'en 1990 au Gabon, un segment d'oléoduc d'une longueur de cinq kilomètres exploité depuis à peine un an a été endommagé par une corrosion localisée dont la vitesse était supérieure à un centimètre par an. Dans ce cas, certaines de ces piqûres de corrosion avaient une largeur de quatre centimètres (Magot et al, 1997). Plus récemment, la littérature rapporte un incident similaire (Samant et al, 1997).…”

“…Pour certaines bactéries, la consommation de ce composé toxique constitue un processus de détoxification. Par ailleurs, certaines bactéries telles que Dethiosulfovibrio peptidovorans sont capables d'utiliser le thiosulfate alors qu'elles n'utilisent pas le sulfate (Magot et al, 1997). Elles constituent le groupe des bactéries thiosulfato-réductrices (BTR).…”

Dethiosulfovibrio salsuginis sp. nov., an anaerobic, slightly halophilic bacterium isolated from a saline spring

“…It was obtained from a corroding offshore oil well in Congo and is a non-saccharolytic peptide-and amino acid-degrading species which grows on several different amino acids in the presence of elemental sulfur or thiosulfate. During such growth, an increase in peptide utilization, cell yields and growth rates has been noted (Magot et al, 1997). In this report, we describe the characterization of a new Dethiosulfovibrio strain, isolated from the 'Salpa' saline spring.…”

“…Confidence in the tree topology was determined by using 1000 bootstrapped trees (Felsenstein, 1985). Phylogenetic analysis placed strain USBA 82 T in the phylum Synergistetes, closest to Dethiosulfovibrio peptidovorans DSM 11002 T (93 % gene sequence similarity) (Magot et al, 1997) (Fig. 1).…”

Activity Inhibition of Sulfate Reducing Bacteria Using Some Cationic Thiol Surfactants and Their Nanostructures

“…The ubiquity of these bacteria leads to a variety of impressive industrial, economic and ecological effects because of their proneness to generate large quantities of H 2 S. Many corrosions of industrial equipment have been ascribed to microbiologically influenced corrosion (MIC) [1,2]. SRB are the main reason to cause the MIC by accelerating corrosion rate, inducing stress corrosion and pitting corrosion [3][4][5]. Previous studies show that the living of SRB accelerate corrosion rate and induce stress corrosion and pitting corrosion of metals [4,5,6] , and put influences on the environment parameters [7], which are possible factors inducing the metal corrosion.…”