title: Thermoanaerobacterium aciditolerans sp. nov., a moderate thermoacidophile from a Kamchatka hot spring.
abstract: An anaerobic, moderately thermoacidophilic bacterium, strain 761-119T, was isolated from an acidic hot spring in the Orange Field of the Uzon Caldera (Kamchatka, far-eastern Russia). Cells were spore-forming, Gram-positive rods, possessing one polar flagellum. Growth of strain 761-119T was observed between 37 and 68 degrees C and in the pH(20 degrees C) range 3.2-7.1. No growth was observed within 5 days of incubation at or below 35 degrees C and at or above 70 degrees C, as well as at or below pH(20 degrees C) 2.8 and at or above pH(20 degrees C) 7.5. The optimal temperature and pH(20 degrees C) for growth were 55 degrees C and pH(20 degrees C) 5.7, respectively. A wide range of carbohydrates and polysaccharides were fermented, as well as peptides and proteinaceous substrates. The main products of glucose fermentation were acetate, ethanol, lactate, H2 and CO2. The DNA G+C content was 34 (+/-0.5) mol%. 16S rRNA gene sequence analysis indicated that strain 761-119T belonged to the genus Thermoanaerobacterium. The level of 16S rRNA gene sequence similarity with other Thermoanaerobacterium species was 86.5-97.8 %, with the only moderately acidophilic member of this genus, Thermoanaerobacterium aotearoense, being one of its closest relatives. DNA-DNA hybridization with T. aotearoense showed 33 % relatedness. Thus, morphological (one polar flagellum) and physiological characteristics (lower pH limit of growth at pH(20 degrees C) 3.2 compared with T. aotearoense) and 16S rRNA gene sequence analyses revealed that strain 761-119T represents a novel species in the genus Thermoanaerobacterium, for which the name Thermoanaerobacterium aciditolerans sp. nov. is proposed, with the type strain 761-119T (=DSM 16487T=VKM B-2363T).
authors.affiliation: Institute of Microbiology, Russian Academy of Sciences, Prospekt 60-Letiya Oktyabrya 7/2, Moscow 117312, Russia.
authors.forename: I V
authors.initials: IV
authors.lastname: Kublanov
authors.affiliation: Institute of Microbiology, Russian Academy of Sciences, Prospekt 60-Letiya Oktyabrya 7/2, Moscow 117312, Russia.
authors.forename: M I
authors.initials: MI
authors.lastname: Prokofeva
authors.affiliation: Institute of Microbiology, Russian Academy of Sciences, Prospekt 60-Letiya Oktyabrya 7/2, Moscow 117312, Russia.
authors.forename: N A
authors.initials: NA
authors.lastname: Kostrikina
authors.affiliation: Bioengineering Center, Russian Academy of Sciences, Prospect 60-Letiya Oktyabrya 7/1, 117312 Moscow, Russia.
authors.forename: T V
authors.initials: TV
authors.lastname: Kolganova
authors.affiliation: Institute of Microbiology, Russian Academy of Sciences, Prospekt 60-Letiya Oktyabrya 7/2, Moscow 117312, Russia.
authors.forename: T P
authors.initials: TP
authors.lastname: Tourova
authors.affiliation: Department of Microbiology, University of Georgia, Athens, GA, USA.
authors.forename: J
authors.initials: J
authors.lastname: Wiegel
authors.affiliation: Institute of Microbiology, Russian Academy of Sciences, Prospekt 60-Letiya Oktyabrya 7/2, Moscow 117312, Russia.
authors.forename: E A
authors.initials: EA
authors.lastname: Bonch-Osmolovskaya
mesh_terms: D019342:Acetic Acid / Q000378:metabolism; D000693:Anaerobiosis; D015373:Bacterial Typing Techniques; D001482:Base Composition; D002245:Carbon Dioxide / Q000378:metabolism; D032084:Citrus sinensis; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D000431:Ethanol / Q000378:metabolism; D005407:Flagella; D020459:Genes, rRNA / Q000235:genetics; D045482:Hot Springs / Q000382:microbiology*; D006859:Hydrogen / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000378:metabolism; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D010455:Peptides / Q000378:metabolism; D010802:Phylogeny; D011134:Polysaccharides / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012426:Russia; D013696:Temperature; D046950:Thermoanaerobacterium / Q000145:classification* / Q000166:cytology / Q000302:isolation & purification* / Q000502:physiology; D014871:Water Microbiology
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D010455:Peptides; D011134:Polysaccharides; D011506:Proteins; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S; D002245:Carbon Dioxide; D019344:Lactic Acid; D000431:Ethanol; D006859:Hydrogen; D019342:Acetic Acid