Thermosipho affectus sp. nov., a thermophilic, anaerobic, cellulolytic bacterium isolated from a Mid-Atlantic Ridge hydrothermal vent.
A novel obligately anaerobic, extremely thermophilic, organotrophic bacterium, strain ik275mar(T), was isolated from a Mid-Atlantic Ridge deep-sea hydrothermal vent. Cells were rods surrounded by a sheath-like structure (toga), 0.4-0.9 µm in width and 1.2-6.0 µm in length. Strain ik275mar(T) grew at 37-75 °C, pH 5.6-8.2 and at NaCl concentrations of 10-55 g l(-1). Under optimum conditions (70 °C, pH 6.6, NaCl 20 g l(-1)), doubling time was 32 min. The isolate was able to ferment carbohydrates including starch, cellulose and cellulose derivatives. Acetate, H(2) and CO(2) were the main products of glucose fermentation. G+C content of DNA was 27 mol%. Phylogenetic analysis of 16S rRNA gene sequences showed that strain ik275mar(T) is a member of the genus Thermosipho. 16S rRNA gene sequence identity with the other species of the genus Thermosipho ranged from 93.7 to 94.5 %. Based on the phylogenetic analysis and physiological properties of the novel isolate, we propose a novel species, Thermosipho affectus sp. nov., with type strain ik275mar(T) ( = DSM 23112(T)  = VKM B-2574(T)).
Podosokorskaya
O A
OA
Winogradsky Institute of Microbiology, Russian Academy of Sciences, Prospekt 60-Letiya Oktyabrya 7/2, 117312 Moscow, Russia.
Kublanov
I V
IV
Winogradsky Institute of Microbiology, Russian Academy of Sciences, Prospekt 60-Letiya Oktyabrya 7/2, 117312 Moscow, Russia.
Reysenbach
A-L
AL
Department of Biology, Portland State University, PO Box 751, Portland, OR 97207-0751, USA.
Kolganova
T V
TV
Bioengineering Center, Russian Academy of Sciences, Prospekt 60-Letiya Oktyabrya 7/1, 117312 Moscow, Russia.
Bonch-Osmolovskaya
E A
EA
Winogradsky Institute of Microbiology, Russian Academy of Sciences, Prospekt 60-Letiya Oktyabrya 7/2, 117312 Moscow, Russia.
D001421:Bacteria, Anaerobic / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D002482:Cellulose / Q000378:metabolism*; D004269:DNA, Bacterial / Q000235:genetics; D005227:Fatty Acids / Q000378:metabolism; D006358:Hot Temperature; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012623:Seawater / Q000382:microbiology*
D004269:DNA, Bacterial; D005227:Fatty Acids; D012336:RNA, Ribosomal, 16S; D002482:Cellulose