HALOANAEROBIUM SALSUGO SP-NOV, A MODERATELY HALOPHILIC, ANAEROBIC BACTERIUM FROM A SUBTERRANEAN BRINE

A strictly anaerobic, moderately halophilic, gram-negative bacterium w as isolated from a highly saline oil field brine. The bacterium was a non-spore-forming, nonmotile rod, appearing singly, in pairs, or occas ionally as long chains, and measured 0.3 to 0.4 by 2.6 to 4 mu m. The bacterium had a specific requirement for NaCl and grew at NaCl concent rations of between 6 and 24%, with optimal growth at 9% NaCl. The isol ate grew at temperatures of between 22 and 51 degrees C and pH values of between 5.6 and 8.0. The doubling time in a complex medium containi ng 10% NaCl was 9 h. Growth was inhibited by chloramphenicol, tetracyc line, and penicillin but not by cycloheximide or azide. Fermentable su bstrates were predominantly carbohydrates. The end products of glucose fermentation were acetate, ethanol, CO2, and H-2. The major component s of the cellular fatty acids were C-14:0, C-16:0, C-16:1, and C-17:0 cyc acids. The DNA base composition of the isolate was 34 mol% G+C. Ol igonucleotide catalog and sequence analyses of the 168 rRNA showed tha t strain VS-752(T) was most closely related to Haloanaerobium praevale ns GSL(T) (ATCC 33744), the sole member of the genus Haloanaerobium. W e propose that strain VS-752 (ATCC 51327) be established as the type s train of a new species, Haloanaerobium salsugo, in the genus Haloanaer obium.