title: Petrotoga mobilis sp. nov., from a North Sea oil-production well.
abstract: Rod-shaped, thermophilic bacteria with a sheath-like outer structure (toga) were isolated from hot oilfield water of a North Sea oil reservoir. One of the isolates, designated SJ95(T), is an obligately anaerobic, sheathed, Gram-negative, fermentative bacterium capable of reducing elemental sulfur to hydrogen sulfide and tolerating high salt concentrations. The optimum growth conditions for this isolate are 58-60 degrees Celsius and pH 6.5-7.0 with 3-4% NaCl and 0.7% MgSO(4). 7H(2)O in the medium. Vitamins are required for growth. Growth is stimulated by yeast extract. Cells of strain SJ95(T) vary in size from 1-2 to 40-50 micron in length and are motile with a subpolar flagellation. Cels grown on xylan have xylanase activity, presumably associated with the toga, and glucose isomerase activity was detected in xylose-grown cells. The DNA G+C content is 31 and 34 mol%, determined by the thermal denaturation and HPLC methods, respectively. Phylogenetically, strain SJ95(T) is most closely related to Petrotoga miotherma with a 97.7% similarity level between their 165 rDNA sequences. The DNA-DNA reassociation value between the two DNAs was 35.6%. On the basis of differences in genotypic, phenotypic and immunological characteristics, strain SJ95t (=DSM 10674t) is proposed as the type strain of a new species, Petrotoga mobilis. It can be readily distinguished from P. miotherma by its motility.
authors.affiliation: Department of Microbiology, University of Bergen, Norway.torleiv.lien@im.uib.no
authors.forename: T
authors.initials: T
authors.lastname: Lien
authors.forename: M
authors.initials: M
authors.lastname: Madsen
authors.forename: F A
authors.initials: FA
authors.lastname: Rainey
authors.forename: N K
authors.initials: NK
authors.lastname: Birkeland
mesh_terms: D001482:Base Composition; D004275:DNA, Ribosomal / Q000737:chemistry; D006089:Gram-Negative Anaerobic Bacteria / Q000145:classification* / Q000302:isolation & purification / Q000502:physiology; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D014871:Water Microbiology
chemical_list: D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S