Alkaliphilus serpentinus sp. nov. and Alkaliphilus pronyensis sp. nov., two novel anaerobic alkaliphilic species isolated from the serpentinite-hosted Prony Bay Hydrothermal Field (New Caledonia).

Two novel anaerobic alkaliphilic strains, designated as LacTT and LacVT, were isolated from the Prony Bay Hydrothermal Field (PBHF, New Caledonia). Cells were motile, Gram-positive, terminal endospore-forming rods, displaying a straight to curved morphology during the exponential phase. Strains LacTT and LacVT were mesophilic (optimum 30°C), moderately alkaliphilic (optimum pH 8.2 and 8.7, respectively) and halotolerant (optimum 2% and 2.5% NaCl, respectively). Both strains were able to ferment yeast extract, peptone and casamino acids, but only strain LacTT could use sugars (glucose, maltose and sucrose). Both strains disproportionated crotonate into acetate and butyrate. Phylogenetic analysis revealed that strains LacTT and LacVT shared 96.4% 16S rRNA gene sequence identity and were most closely related to A. peptidifermentans Z-7036, A. namsaraevii X-07-2 and A. hydrothermalis FatMR1 (95.7%-96.3%). Their genome size was of 3.29Mb for strain LacTT and 3.06Mb for strain LacVT with a G+C content of 36.0 and 33.9mol%, respectively. The ANI value between both strains was 73.2 %. Finally, strains LacTT (=DSM 100337=JCM 30643) and LacVT (=DSM 100017=JCM 30644) are proposed as two novel species of the genus Alkaliphilus, order Clostridiales, phylum Firmicutes, Alkaliphilus serpentinus sp. nov. and Alkaliphilus pronyensis sp. nov., respectively. The genomes of the three Alkaliphilus species isolated from PBHF were consistently detected in the PBHF chimney metagenomes, although at very low abundance, but not significantly in the metagenomes of other serpentinizing systems (marine or terrestrial) worldwide, suggesting they represent indigenous members of the PBHF microbial ecosystem.

Characterization of Peptacetobacter hominis gen. nov., sp. nov., isolated from human faeces, and proposal for the reclassification of Clostridium hiranonis within the genus Peptacetobacter.

A novel, Gram-stain-positive, rod-shaped, non-motile, non-spore-forming, obligately anaerobic bacterium, designated strain ZHW00191T, was isolated from human faeces and characterized by using a polyphasic taxonomic approach. Growth occurred at 25-45 °C (optimum, 37-42 °C), at pH 5.5-10.0 (optimum, pH 6.5-7.0) and with 0-2 % (w/v) NaCl (optimum, 0 %). The end products of glucose fermentation were acetic acid, isobutyric acid and isovaleric acid and a small amount of propionic acid. The dominant cellular fatty acids (>10 %) of strain ZHW00191T were C16 : 0, C18 : 1 ω9с and C18 : 2ω6,9с. Its polar lipid profile comprised diphosphatidylglycerol, phosphatidylglycerol, three unidentified phospholipids and ten unidentified glycolipids. Respiratory quinones were not detected. The cell-wall peptidoglycan contained meso-2,6-diaminopimelic acid, and the whole-cell sugars were ribose and glucose. The genomic DNA G+C content was 32.8 mol%. Analysis of the 16S rRNA gene sequence indicated that ZHW00191T was most closely related to Clostridium hiranonis TO-931T (95.3 % similarity). Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) analyses with closely related reference strains indicated that reassociation values were both well below the thresholds of 95-96% and 70 % for species delineation, respectively. Based on phenotypic, chemotaxonomic and genetic studies, a novel genus, Peptacetobacter gen. nov., is proposed. The novel isolate ZHW00191T (=JCM 33482T=GDMCC 1.1530T) is proposed as the type strain of the type species Peptacetobacter hominis gen. nov., sp. nov. of the proposed new genus. Furthermore, it is proposed that Clostridium hiranonis be transferred to this novel genus, as Peptacetobacter hiranonis comb. nov.

Romboutsia sedimentorum sp. nov., isolated from an alkaline-saline lake sediment and emended description of the genus Romboutsia.

A Gram-stain-positive, spore-forming, obligately anaerobic bacterium, designated LAM201(T), was isolated from sediment samples from an alkaline-saline lake located in Daqing oilfield, Daqing City, PR China. Cells of strain LAM201(T) were non-motile and straight or spiral rod-shapes. Strain LAM201(T) was able to utilize glucose, fructose, maltose, trehalose and sorbitol as the sole carbon source. Acetic acid, ethanol, iso-butanoic acid and iso-valeric acid were the main products of glucose fermentation. The major fatty acids of LAM201(T) were C(16 : 0) (26.7%) and C(18 : 0) (11.2%). The main polar lipids were four unknown glycolipids and five unknown phospholipids. The predominant cell-wall sugars were ribose and galactose. The cell-wall peptidoglycan of strain LAM201(T) contained alanine, glycine, glutamic acid and aspartic acid. Sodium sulfite was used as the electron acceptor. The G+C content of the genomic DNA was 32±0.8 mol%, as determined by the T(m) method. Analysis of the 16S rRNA gene sequence indicated that the isolate belonged to the genus Romboutsia and was most closely related to Romboutsia lituseburensis DSM 797(T) and Romboutsia ilealis CRIB(T) with 97.3% and 97.2% similarities, respectively. The DNA-DNA hybridization values between strain LAM201(T) and the two reference strains were 37% and 31%, respectively. On the basis of its phenotypic, phylogenetic and chemotaxonomic characteristics, strain LAM201(T) is suggested to represent a novel species within the genus Romboutsia , for which the name Romboutsia sedimentorum sp. nov. is proposed. The type strain is LAM201(T) ( = ACCC 00717(T) = JCM 19607(T)).

Modulation of fecal Clostridiales bacteria and butyrate by probiotic intervention with Lactobacillus paracasei DG varies among healthy adults.

BACKGROUND: The modulation of gut microbiota is considered to be the first target to establish probiotic efficacy in a healthy population. OBJECTIVE: This study was conducted to determine the impact of a probiotic on the intestinal microbial ecology of healthy volunteers. METHODS: High-throughput 16S ribosomal RNA gene sequencing was used to characterize the fecal microbiota in healthy adults (23-55 y old) of both sexes, before and after 4 wk of daily consumption of a capsule containing at least 24 billion viable Lactobacillus paracasei DG cells, according to a randomized, double-blind, crossover placebo-controlled design. RESULTS: Probiotic intake induced an increase in Proteobacteria (P = 0.006) and in the Clostridiales genus Coprococcus (P = 0.009), whereas the Clostridiales genus Blautia (P = 0.036) was decreased; a trend of reduction was also observed for Anaerostipes (P = 0.05) and Clostridium (P = 0.06). We also found that the probiotic effect depended on the initial butyrate concentration. In fact, participants with butyrate >100 mmol/kg of wet feces had a mean butyrate reduction of 49 ± 21% and a concomitant decrease in the sum of 6 Clostridiales genera, namely Faecalibacterium, Blautia, Anaerostipes, Pseudobutyrivibrio, Clostridium, and Butyrivibrio (P = 0.021), after the probiotic intervention. In contrast, in participants with initial butyrate concentrations <25 mmol/kg of wet feces, the probiotic contributed to a 329 ± 255% (mean ± SD) increment in butyrate concomitantly with an ∼55% decrease in Ruminococcus (P = 0.016) and a 150% increase in an abundantly represented unclassified Bacteroidales genus (P = 0.05). CONCLUSIONS: The intake of L. paracasei DG increased the Blautia:Coprococcus ratio, which, according to the literature, can potentially confer a health benefit on the host. The probiotic impact on the microbiota and on short-chain fatty acids, however, seems to strictly depend on the initial characteristics of the intestinal microbial ecosystem. In particular, fecal butyrate concentrations could represent an important biomarker for identifying subjects who may benefit from probiotic treatment. This trial was registered at www.controlled-trials.com/isrctn as ISRCTN56945491.

Aneurinibacillus soli sp. nov., isolated from mountain soil.

A novel bacterial strain designated CB4(T) was isolated from soil from the Hallasan, Jeju, Korea. Strain CB4(T) was found to be strictly aerobic, Gram-stain-positive, rod-shaped, motile and formed creamy greyish colonies on nutrient agar. The major fatty acids were identified as iso-C(15:0) and iso-C(16:0), and the predominant isoprenoid quinone as MK-7. The cell-wall peptidoglycan contained glycine and alanine as the diagnostic amino acids and phosphatidyl-N-methylethanolamine, phosphatidylethanolamine, diphosphatidylglycerol and an unidentified aminophospholipid as the polar lipids. The genomic DNA G+C content of strain CB4(T) was 46.5 mol%. Phylogenetic analysis, based on 16S rRNA gene sequence similarities, showed that strain CB4(T) forms a deep branch within the genus Aneurinibacillus, sharing the highest level of sequence homology with Aneurinibacillus aneurinilyticus DSM 5562(T) (96.5%). On the basis of the phenotypic, chemotaxonomic and phylogenetic characteristics, strain CB4(T) is considered to represent a novel species within the genus Aneurinibacillus, for which the name Aneurinibacillus soli sp. nov. is proposed. The type strain is CB4(T) ( =KCTC 33505(T) =CECT 8566(T)). An emended description of the genus Aneurinibacillus is also proposed.

Description of Symbiobacterium ostreiconchae sp. nov., Symbiobacterium turbinis sp. nov. and Symbiobacterium terraclitae sp. nov., isolated from shellfish, emended description of the genus Symbiobacterium and proposal of Symbiobacteriaceae fam. nov.

Three novel moderately anaerobic, thermophilic, rod-shaped bacterial strains, KY38(T), KY46(T) and KA13(T), were isolated from shellfish collected on the Pacific coastline of Enoshima, Japan. Phylogenetic analysis of the 16S rRNA gene sequences indicated that these bacteria belong to the genus Symbiobacterium, sharing sequence similarities of 97.8% (KY38(T)), 96.4% (KY46(T)) and 93.3% (KA13(T)) with the type strain of Symbiobacterium thermophilum, the only species of the genus with a validly published name. These isolates reduced nitrate and grew optimally at 55-60 °C. Strains KY38(T) and KA13(T) formed endospore-like structures in the terminal or subterminal part of their cells at low frequencies. Genomic DNA G+C contents were 68.8 (KY38(T)), 67.2 (KY46(T)) and 67.1 (KA13(T)) mol%. The isolates all presented the predominant menaquinone MK-6, major fatty acids iso-C15:0, C16:0 and iso-C17:0 and the major polar lipids phosphatidylglycerol, phosphatidylethanolamine and unknown glycol-containing phospholipids. On the basis of their morphological, physiological and phylogenetic properties, strains KY38(T), KY46(T) and KA13(T) represent three novel species, for which the names Symbiobacterium ostreiconchae sp. nov. (type strain KY38(T) = DSM 27624(T) = KCTC 4567(T) = JCM 15048(T)), Symbiobacterium turbinis sp. nov. (type strain KY46(T) = DSM 27625(T) = KCTC 4568(T) = JCM 15996(T)) and Symbiobacterium terraclitae sp. nov. (type strain KA13(T) = DSM 27138(T) = KCTC 4569(T) = JCM 15997(T)) are proposed. An emended description of the genus Symbiobacterium is also presented. The phylogenetic distinctiveness of the genus Symbiobacterium indicates its affiliation with a novel family, for which the name Symbiobacteriaceae fam. nov. is proposed.

Mobilitalea sibirica gen. nov., sp. nov., a halotolerant polysaccharide-degrading bacterium.

A novel strictly anaerobic, halotolerant, organotrophic bacterium, strain P3M-3(T), was isolated from a microbial mat formed under the flow of hot water emerging from a 2775 m-deep well in Tomsk region (western Siberia, Russia). Cells of strain P3M-3(T) were straight and curved rods, 0.2-0.4 µm in width and 1.5-20 µm in length. Strain P3M-3(T) grew optimally at 37 °C, pH 7.0-7.5 and in a NaCl concentration of 15 g l(-1). Under optimum growth conditions, the doubling time was 1 h. The isolate was able to ferment a variety of mono-, di- and polysaccharides, including microcrystalline cellulose. Acetate, ethanol, H2 and CO2 were the main products of glucose fermentation. The DNA G+C content was 33.4 mol%. 16S rRNA gene-based phylogenetic analysis showed that strain P3M-3(T) was a member of family Lachnospiraceae, whose representatives are also found in Clostridium cluster XIVa. 16S rRNA gene sequence similarity with Clostridium jejuense HY-35-12(T), the closest relative, was 93.9%. A novel genus and species, Mobilitalea sibirica gen. nov., sp. nov., are proposed based on phylogenetic analysis and physiological properties of the novel isolate. The type strain of the type species is P3M-3(T) ( = DSM 26468(T) = VKM B-2804(T)).

Characterization of Romboutsia ilealis gen. nov., sp. nov., isolated from the gastro-intestinal tract of a rat, and proposal for the reclassification of five closely related members of the genus Clostridium into the genera Romboutsia gen. nov., Intestinibacter gen. nov., Terrisporobacter gen. nov. and Asaccharospora gen. nov.

A Gram-positive staining, rod-shaped, non-motile, spore-forming obligately anaerobic bacterium, designated CRIBT, was isolated from the gastro-intestinal tract of a rat and characterized. The major cellular fatty acids of strain CRIBT were saturated and unsaturated straight-chain C12-C19 fatty acids, with C16:0 being the predominant fatty acid. The polar lipid profile comprised six glycolipids, four phospholipids and one lipid that did not stain with any of the specific spray reagents used. The only quinone was MK-6. The predominating cell-wall sugars were glucose and galactose. The peptidoglycan type of strain CRIBT was A1σ lanthionine-direct. The genomic DNA G+C content of strain CRIBT was 28.1 mol%. On the basis of 16S rRNA gene sequence similarity, strain CRIBT was most closely related to a number of species of the genus Clostridium, including Clostridium lituseburense (97.2%), Clostridium glycolicum (96.2%), Clostridium mayombei (96.2%), Clostridium bartlettii (96.0%) and Clostridium irregulare (95.5%). All these species show very low 16S rRNA gene sequence similarity (<85%) to the type strain of Clostridium butyricum, the type species of the genus Clostridium. DNA-DNA hybridization with closely related reference strains indicated reassociation values below 32%. On the basis of phenotypic and genetic studies, a novel genus, Romboutsia gen. nov., is proposed. The novel isolate CRIBT (=DSM 25109T=NIZO 4048T) is proposed as the type strain of the type species, Romboutsia ilealis gen. nov., sp. nov., of the proposed novel genus. It is proposed that C. lituseburense is transferred to this genus as Romboutsia lituseburensis comb. nov. Furthermore, the reclassification into novel genera is proposed for C. bartlettii, as Intestinibacter bartlettii gen. nov., comb. nov. (type species of the genus), C. glycolicum, as Terrisporobacter glycolicus gen. nov., comb. nov. (type species of the genus), C. mayombei, as Terrisporobacter mayombei gen. nov., comb. nov., and C. irregulare, as Asaccharospora irregularis gen. nov., comb. nov. (type species of the genus), on the basis of additional data collected in this study. In addition, an emendation of the species Peptostreptococcus anaerobius and the order Eubacteriales is provided.

Hungatella effluvii gen. nov., sp. nov., an obligately anaerobic bacterium isolated from an effluent treatment plant, and reclassification of Clostridium hathewayi as Hungatella hathewayi gen. nov., comb. nov.

A Gram-stain-positive, rod-shaped, spore-forming and strictly anaerobic bacterium, designated UB-B.2(T), was isolated from an industrial effluent anaerobic digester sample. It grew optimally at 30 °C and pH 7.0. Comparative analysis of the 16S rRNA gene sequence confirmed that strain UB-B.2(T) was closely related to Clostridium hathewayi DSM 13479(T) (97.84% similarity), a member of rRNA gene cluster XIVa of the genus Clostridium, and formed a coherent cluster with other related members of the Blautia (Clostridium) coccoides rRNA group in phylogenetic analyses. The end products of glucose fermentation by strain UB-B.2(T) were acetate and propionate. The G+C content of the DNA was 51.4 mol%. Although strain UB-B.2(T) showed 97.8% 16S rRNA gene sequence identity to the type strain of C. hathewayi, it exhibited only 38.4% relatedness at the whole-genome level. It also showed differences from its closest phylogenetic relative, C. hathewayi DSM 13479(T), in phenotypic characteristics such as hydrolysis of aesculin, starch and urea and fermentation end products. Both strains showed phenotypic differences from the members of rRNA gene cluster XIVa of the genus Clostridium. Based on these differences, C. hathewayi DSM 13479(T) and strain UB-B.2(T) were identified as representatives of a new genus of the family Clostridiaceae. Thus, we propose the reclassification of Clostridium hathewayi as Hungatella hathewayi gen. nov., comb. nov., the type species of the new genus (type strain DSM 13479(T) = CCUG 43506(T) = MTCC 10951(T)). Strain UB-B.2(T) ( = MTCC 11101(T) = DSM 24995(T)) is assigned to the novel species Hungatella effluvii gen. nov., sp. nov as the type strain.

Anaerostipes rhamnosivorans sp. nov., a human intestinal, butyrate-forming bacterium.

A novel butyrate-producing bacterium, strain 1y-2(T), was isolated from a stool sample of a 1-year-old, healthy Dutch infant. The isolate was obtained by using lactate and acetate as sources of carbon and energy. The strain was Gram-variable, strictly anaerobic and spore-forming and formed curly rod-shaped cells that fermented glucose into butyrate, lactate, formate and acetate as main products. The DNA G+C content of the strain was 44.5 mol% and its major cellular fatty acids were C12:0, iso-C19:1 I and C16:0. Strain 1y-2(T) was related to Anaerostipes caccae DSM 14662(T) based on 16S rRNA gene sequence analysis, with 3% divergence, but hybridization studies of their genomic DNA revealed only 33% relatedness. Moreover, strain 1y-2(T) showed marked physiological and biochemical differences from known species of the genus Anaerostipes. Based on phylogenetic, chemotypic and phenotypic criteria, we propose that strain 1y-2(T) should be classified in the genus Anaerostipes within a novel species, Anaerostipes rhamnosivorans sp. nov. The type strain is 1y-2(T) ( = DSM 26241(T) = KCTC 15316(T)).

Intestinimonas butyriciproducens gen. nov., sp. nov., a butyrate-producing bacterium from the mouse intestine.

A Gram-positive, spore-forming, non-motile, strictly anaerobic rod-shaped bacterium was isolated from the caecal content of a TNF(deltaARE) mouse. The isolate, referred to as strain SRB-521-5-I(T), was originally cultured on a reduced agar medium containing yeast extract, rumen fluid and lactic acid as main energy and carbon sources. Phylogenetic analysis of partial 16S rRNA genes revealed that the species most closely related to strain SRB-521-5-I(T) were Flavonifractor plautii and Pseudoflavonifractor capillosus (<95 % sequence similarity; 1436 bp). In contrast to F. plautii and P. capillosus, strain SRB-521-5-I(T) contained a substantial amount of C18 : 0 dimethylacetal. Additional major fatty acids were C14 : 0 methyl ester, C16 : 0 dimethylacetal and C18 : 0 aldehyde. Strain SRB-521-5-I(T) differed in its enzyme profile from F. plautii and P. capillosus by being positive for dextrin, maltotriose, turanose, dl-lactic acid and d-lactic acid methyl ester but negative for d-fructose. In reduced Wilkins-Chalgren-Anaerobe broth, strain SRB-521-5-I(T) produced approximately 8 mM butyrate and 4 mM acetate. In contrast to F. plautii, the strain did not metabolize flavonoids. It showed intermediate resistance towards the antibiotics ciprofloxacin, colistin and tetracycline. Based on genotypic and phenotypic characteristics, we propose the name Intestinimonas butyriciproducens gen. nov., sp. nov. to accommodate strain SRB-521-5-I(T) ( = DSM 26588(T) = CCUG 63529(T)) as the type strain.

Oceanirhabdus sediminicola gen. nov., sp. nov., an anaerobic bacterium isolated from sea sediment.

A novel anaerobic bacterium, designated NH-JN4(T) was isolated from a sediment sample collected in the South China Sea. Cells were Gram-stain-positive, spore-forming, peritrichous and rod-shaped (0.5-1.2×2.2-7 µm). The temperature and pH ranges for growth were 22-42 °C and pH 6.0-8.5. Optimal growth occurred at 34-38 °C and pH 6.5-7.0. The NaCl concentration range for growth was 0.5-6 % (w/v) with an optimum of 2.5 %. Catalase and oxidase were not produced. Substrates which could be utilized were peptone, tryptone, yeast extract, beef extract and glycine. Main fermentation products from PYG medium were formate, acetate, butyrate and ethanol. Strain NH-JN4(T) could utilize sodium sulfite as an electron acceptor. No respiratory quinone was detected. The predominant fatty acids were anteiso-C15 : 0, C16 : 0, iso-C15 : 0, anteiso-C17 : 0 and C16 : 0 DMA. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and glycolipids. The DNA G+C content was 35.8 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain NH-JN4(T) was a member of family Clostridiaceae, and was most closely related to Clostridium limosum ATCC 25620(T), Clostridium proteolyticum DSM 3090(T), Clostridium histolyticum ATCC 19401(T) and Clostridium tepidiprofundi SG 508(T), showing 94.0, 93.0, 92.9 and 92.3 % sequence similarity, respectively. On the basis of phenotypic, genotypic and chemotaxonomic properties, strain NH-JN4(T) represents a novel species of a new genus in the family Clostridiaceae, for which the name Oceanirhabdus sediminicola gen. nov., sp. nov. is proposed. The type strain of the type species is NH-JN4(T) ( = JCM 18501(T) = CCTCC AB 2013103(T) = KCTC 15322(T)).

Natranaerobaculum magadiense gen. nov., sp. nov., an anaerobic, alkalithermophilic bacterium from soda lake sediment.

An obligately alkaliphilic, anaerobic, thermo- and halotolerant, spore-forming bacterium was isolated from sediments of soda lake Magadi (Kenya) and designated strain Z-1001(T). Cells of strain Z-1001(T) were straight, Gram-positive rods, slowly motile. Strain Z-1001(T) was found to be an obligate anaerobe. It grew within a pH range from 7.5 to 10.7 with an optimum at 9.25-9.5 (at 40 °C), a temperature range from 20 to 57 °C with an optimum at 45-50 °C, and a NaCl concentration range from 0 to 1.55 M with an optimum at 1.2-1.4 M. Peptides, such as meat and yeast extracts, peptone and tryptone, were fermented by Z-1001(T). Carbohydrates did not support growth. With yeast extract as an electron donor, strain Z-1001(T) reduced S(2)O(3)(2-), NO(-)(3), AsO(3-)(4), Fe(III) citrate and anthraquinone-2,6-disulfonate (AQDS) as electron acceptors. The isolate was able to grow oligotrophically with a very small amount of yeast extract: 0.03 g l(-1). The main fatty acids were C16 : 0, C16 : 1ω7c, C18 : 0 and C18 : 1ω9. The DNA G+C content of the isolate was 35.6 mol%. 16S rRNA gene sequence analysis showed that strain Z-1001(T) is a member of family Natranaerobiaceae, clustering with the type strain of Natranaerobius thermophilus (95.8-96.0 % sequence similarity). On the basis of physiological and phylogenetic data it is proposed that strain Z-1001(T) ( = DSM 24923(T) = VKM B-2666(T)) represents a novel genus and species, Natranaerobaculum magadiense gen. nov., sp. nov.

Pullulanibacillus uraniitolerans sp. nov., an acidophilic, U(VI)-resistant species isolated from an acid uranium mill tailing effluent and emended description of the genus Pullulanibacillus.

Two Gram-positive-staining, rod-shaped, endospore-forming isolates (UG-2(T) and UG-3), with an optimum growth temperature of around 37 °C and an optimum pH for growth of about 4, were recovered from an acidic effluent of the uranium mill tailing at Urgeiriça in Central Portugal. On the basis of 16S rRNA gene sequence similarity, the strains belonged to the family Sporolactobacillaceae and were closely related to Pullulanibacillus naganoensis ATCC 53909(T) (97.9 %). Unlike P. naganoensis, strains UG-2(T) and UG-3 grew in medium containing up to 5000 p.p.m. U(VI) but did not hydrolyse pullulan. Chemotaxonomic data also supported the affiliation of strains UG-2(T) and UG-3 to the genus Pullulanibacillus. Physiological and biochemical tests along with fatty acid composition allowed differentiation of strains UG-2(T) and UG-3 from P. naganoensis. It is suggested that strains UG-2(T) and UG-3 represent a novel species, for which the name Pullulanibacillus uraniitolerans is proposed; the type strain is UG-2(T) (=DSM 19429(T) = LMG 24205(T)). An emended description of the genus Pullulanibacillus is also proposed.

Microbiota conservation and BMI signatures in adult monozygotic twins.

The human gastrointestinal (GI) tract microbiota acts like a virtual organ and is suggested to be of great importance in human energy balance and weight control. This study included 40 monozygotic (MZ) twin pairs to investigate the influence of the human genotype on GI microbiota structure as well as microbial signatures for differences in body mass index (BMI). Phylogenetic microarraying based on 16S rRNA genes demonstrated that MZ twins have more similar microbiotas compared with unrelated subjects (P<0.001), which allowed the identification of 35 genus-like microbial groups that are more conserved between MZ twins. Half of the twin pairs were selected on discordance in terms of BMI, which revealed an inverse correlation between Clostridium cluster IV diversity and BMI. Furthermore, relatives of Eubacterium ventriosum and Roseburia intestinalis were positively correlated to BMI differences, and relatives of Oscillospira guillermondii were negatively correlated to BMI differences. Lower BMI was associated with a more abundant network of primary fiber degraders, while a network of butyrate producers was more prominent in subjects with higher BMI. Combined with higher butyrate and valerate contents in the fecal matter of higher BMI subjects, the difference in microbial networks suggests a shift in fermentation patterns at the end of the colon, which could affect human energy homeostasis.

The isolation, identification of sludge-lysing thermophilic bacteria and its utilization in solubilization for excess sludge.

A novel strain of thermophilic bacteria with a highly efficient sludge dissolution performance was isolated from garden soil at 65 degrees C in this study. The colony morphology, physiological and biochemical characteristics of the strain were investigated. The results showed that the strain was Gram-positive, small rod-shaped, sporulating and secreted extracellular enzymes (protease and amylase). The 16S rDNA analysis demonstrated that this strain had not been previously reported. Therefore, it was labelled Bacillus thermophilic bacteria AT07-1 (registration number: FJ231108). To evaluate its capability for excess sludge solubilization, a pure culture of the strain was used in sludge solubilization tests; an enhanced solubilization process was subsequently obtained. After 36 h digestion, the protease activity in the inoculated system reached 0.37 U/ml, an increase of 0.16 U/ml compared with the non-inoculated system (0.21 U/ml). The solubilization rate for volatile suspended solids reached 46.45% in 48 h after inoculation with Bacillus thermophilic bacteria AT07-1, which was 10.24% higher than the non-inoculated system, and which could meet the standard of sludge stability suggested by the US Environmental Protection Agency.

Amino acid-assimilating phototrophic heliobacteria from soda lake environments: Heliorestis acidaminivorans sp. nov. and 'Candidatus Heliomonas lunata'.

Two novel taxa of heliobacteria, Heliorestis acidaminivorans sp. nov. strain HR10B(T) and 'Candidatus Heliomonas lunata' strain SLH, were cultured from shoreline sediments/soil of Lake El Hamra (Egypt) and lake water/benthic sediments of Soap Lake (USA), respectively; both are highly alkaline soda lakes. Cells of strain HR10B were straight rods, while cells of strain SLH were curved rods. Both organisms were obligate anaerobes, produced bacteriochlorophyll g, and lacked intracytoplasmic photosynthetic membrane systems. Although the absorption spectrum of strain HR10B was typical of other heliobacteria, that of strain SLH showed unusually strong absorbance of the OH-chlorophyll a component. Major carotenoids of both organisms were OH-diaponeurosporene glucosyl esters, as in other alkaliphilic heliobacteria, and both displayed an alkaliphilic and mesophilic phenotype. Strain HR10B was remarkable among heliobacteria in its capacity to photoassimilate a number of carbon sources, including several amino acids. Nitrogenase activity was observed in strain HR10B, but not in strain SLH. The 16S ribosomal RNA gene tree placed strain HR10B within the genus Heliorestis, but distinct from other described species. By contrast, strain SLH was phylogenetically more closely related to neutrophilic heliobacteria and is the first alkaliphilic heliobacterium known outside of the genus Heliorestis.

Cohnella cellulosilytica sp. nov., isolated from buffalo faeces.

A cellulose-degrading bacterium, strain FCN3-3(T), was isolated from buffalo faeces collected in Nakhonnayok province, Thailand. The strain was characterized based on its phenotypic and genotypic characteristics. Strain FCN3-3(T) was a Gram-positive, aerobic, spore-forming, rod-shaped bacterium. It contained meso-diaminopimelic acid in cell-wall peptidoglycan. The major menaquinone was MK-7. Anteiso-C(15:0) (52.5%), iso-C(16:0) (18.9%) and C(16:0) (9.1%) were the predominant cellular fatty acids, and diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and lysyl-phosphatidylglycerol were the major phospholipids. The DNA G+C content was 58.0 mol%. Phylogenetic analysis using 16S rRNA gene sequences showed that strain FCN3-3(T) was affiliated to the genus Cohnella and was closely related to Cohnella phaseoli GSPC1(T), Cohnella luojiensis HY-22R(T) and Cohnella hongkongensis HKU3(T), with 97.2, 96.8 and 96.3% sequence similarity, respectively. Strain FCN3-3(T) could be clearly distinguished from all known species of the genus Cohnella by its physiological and biochemical characteristics as well as its phylogenetic position and level of DNA-DNA relatedness. Therefore, the strain represents a novel species of the genus Cohnella, for which the name Cohnella cellulosilytica sp. nov. is proposed; the type strain is FCN3-3(T) ( = KCTC 13645(T) = TISTR 1996(T) = PCU 323(T)).

Sporosarcina newyorkensis sp. nov. from clinical specimens and raw cow's milk.

Twelve independent isolates of a gram-positive, endospore-forming rod were recovered from clinical specimens in New York State, USA, and from raw milk in Flanders, Belgium. The 16S rRNA gene sequences for all isolates were identical. The closest species with a validly published name, based on 16S rRNA gene sequence, is Sporosarcina koreensis (97.13 % similarity). DNA-DNA hybridization studies demonstrate that the new isolates belong to a species distinct from their nearest phylogenetic neighbours. The partial sequences of the 23S rRNA gene for the novel strains and their nearest neighbours also provide support for the novel species designation. Maximum-likelihood phylogenetic analysis of the 16S rRNA gene sequences confirmed that the new isolates are in the genus Sporosarcina. The predominant menaquinone is MK-7, the peptidoglycan has the type A4α L-Lys-Gly-D-Glu, and the polar lipids consist of diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The predominant fatty acids are iso-C(14 : 0), iso-C(15 : 0) and anteiso-C(15 : 0). In addition, biochemical and morphological analyses support designation of the twelve isolates as representatives of a single new species within the genus Sporosarcina, for which the name Sporosarcina newyorkensis sp. nov. (type strain 6062(T)  = DSM 23544(T)  = CCUG 59649(T)  = LMG 26022(T)) is proposed.

Complete genome sequence of the cellulose-degrading bacterium Cellulosilyticum lentocellum.

Cellulosilyticum lentocellum DSM 5427 is an anaerobic, endospore-forming member of the Firmicutes. We describe the complete genome sequence of this cellulose-degrading bacterium, which was originally isolated from estuarine sediment of a river that received both domestic and paper mill waste. Comparative genomics of cellulolytic clostridia will provide insight into factors that influence degradation rates.