scholarly journals Caldicellulosiruptor obsidiansis sp. nov., an Anaerobic, Extremely Thermophilic, Cellulolytic Bacterium Isolated from Obsidian Pool, Yellowstone National Park

2009 ◽  
Vol 76 (4) ◽  
pp. 1014-1020 ◽  
Author(s):  
Scott D. Hamilton-Brehm ◽  
Jennifer J. Mosher ◽  
Tatiana Vishnivetskaya ◽  
Mircea Podar ◽  
Sue Carroll ◽  
...  

ABSTRACT A novel, obligately anaerobic, extremely thermophilic, cellulolytic bacterium, designated OB47T, was isolated from Obsidian Pool, Yellowstone National Park, WY. The isolate was a nonmotile, non-spore-forming, Gram-positive rod approximately 2 μm long by 0.2 μm wide and grew at temperatures between 55 and 85°C, with the optimum at 78°C. The pH range for growth was 6.0 to 8.0, with values of near 7.0 being optimal. Growth on cellobiose produced the fastest specific growth rate at 0.75 h−1. The organism also displayed fermentative growth on glucose, maltose, arabinose, fructose, starch, lactose, mannose, sucrose, galactose, xylose, arabinogalactan, Avicel, xylan, filter paper, processed cardboard, pectin, dilute acid-pretreated switchgrass, and Populus. OB47T was unable to grow on mannitol, fucose, lignin, Gelrite, acetate, glycerol, ribose, sorbitol, carboxymethylcellulose, and casein. Yeast extract stimulated growth, and thiosulfate, sulfate, nitrate, and sulfur were not reduced. Fermentation end products were mainly acetate, H2, and CO2, although lactate and ethanol were produced in 5-liter batch fermentations. The G+C content of the DNA was 35 mol%, and sequence analysis of the small subunit rRNA gene placed OB47T within the genus Caldicellulosiruptor. Based on its phylogenetic and phenotypic properties, the isolate is proposed to be designated Caldicellulosiruptor obsidiansis sp. nov. and OB47 is the type strain (ATCC BAA-2073).

2009 ◽  
Vol 75 (13) ◽  
pp. 4565-4572 ◽  
Author(s):  
Scott R. Miller ◽  
Aaron L. Strong ◽  
Kenneth L. Jones ◽  
Mark C. Ungerer

ABSTRACT An understanding of how communities are organized is a fundamental goal of ecology but one which has historically been elusive for microbial systems. We used a bar-coded pyrosequencing approach targeting the V3 region of the bacterial small-subunit rRNA gene to address the factors that structure communities along the thermal gradients of two alkaline hot springs in the Lower Geyser Basin of Yellowstone National Park. The filtered data set included a total of nearly 34,000 sequences from 39 environmental samples. Each was assigned to one of 391 operational taxonomic units (OTUs) identified by their unique V3 sequence signatures. Although the two hot springs differed in their OTU compositions, community resemblance and diversity changed with strikingly similar dynamics along the two outflow channels. Two lines of evidence suggest that these community properties are controlled primarily by environmental temperature. First, community resemblance decayed exponentially with increasing differences in temperature between samples but was only weakly correlated with physical distance. Second, diversity decreased with increasing temperature at the same rate along both gradients but was uncorrelated with other measured environmental variables. This study also provides novel insights into the nature of the ecological interactions among important taxa in these communities. A strong negative association was observed between cyanobacteria and the Chloroflexi, which together accounted for ∼70% of the sequences sampled. This pattern contradicts the longstanding hypothesis that coadapted lineages of these bacteria maintain tightly cooccurring distributions along these gradients as a result of a producer-consumer relationship. We propose that they instead compete for some limiting resource(s).


2002 ◽  
Vol 68 (10) ◽  
pp. 5123-5135 ◽  
Author(s):  
Carrine E. Blank ◽  
Sherry L. Cady ◽  
Norman R. Pace

ABSTRACT The extent of hyperthermophilic microbial diversity associated with siliceous sinter (geyserite) was characterized in seven near-boiling silica-depositing springs throughout Yellowstone National Park using environmental PCR amplification of small-subunit rRNA genes (SSU rDNA), large-subunit rDNA, and the internal transcribed spacer (ITS). We found that Thermocrinis ruber, a member of the order Aquificales, is ubiquitous, an indication that primary production in these springs is driven by hydrogen oxidation. Several other lineages with no known close relatives were identified that branch among the hyperthermophilic bacteria. Although they all branch deep in the bacterial tree, the precise phylogenetic placement of many of these lineages is unresolved at this time. While some springs contained a fair amount of phylogenetic diversity, others did not. Within the same spring, communities in the subaqueous environment were not appreciably different than those in the splash zone at the edge of the pool, although a greater number of phylotypes was found along the pool's edge. Also, microbial community composition appeared to have little correlation with the type of sinter morphology. The number of cell morphotypes identified by fluorescence in situ hybridization and scanning electron microscopy was greater than the number of phylotypes in SSU clone libraries. Despite little variation in Thermocrinis ruber SSU sequences, abundant variation was found in the hypervariable ITS region. The distribution of ITS sequence types appeared to be correlated with distinct morphotypes of Thermocrinis ruber in different pools. Therefore, species- or subspecies-level divergences are present but not detectable in highly conserved SSU sequences.


2021 ◽  
Author(s):  
Ayaka Takahashi ◽  
Hisaya Kojima ◽  
Miho Watanabe ◽  
Manabu Fukui

Abstract A novel mesophilic and neutrophilic sulfate-reducing bacterium, strain SF6T, was isolated from sediment of a brackish lake in Japan. Cells of strain SF6T were motile and rod-shaped with length of 1.2–2.5 μm and width of 0.6–0.9 μm. Growth was observed at 10–37°C with an optimum growth temperature of 28°C. The pH range for growth was 5.8–8.2 with an optimum pH of 7.0. The most predominant fatty acid was anteiso-C15 : 0. Under sulfate-reducing conditions, strain SF6T utilized formate, lactate, ethanol and glucose as growth substrate. Chemolithoautotrophic growth on H2 was also observed. Fermentative growth occurred on pyruvate. As electron acceptor, sulfate, sulfite, thiosulfate and nitrate supported heterotrophic growth of the strain. The complete genome of strain SF6T is composed of a circular chromosome with length of 3.8 Mbp and G + C content of 54 mol%. Analyses of the 16S rRNA gene and whole genome sequence indicated that strain SF6T belongs to the genus Pseudodesulfovibrio but distinct form all existing species in the genus. On the basis of its genomic and phenotypic properties, strain SF6T (= DSM111931T = NBRC 114895T) is proposed as the type strain of a new species, with name of Pseudodesulfovibrio sediminis sp. nov.


2020 ◽  
Vol 9 (1) ◽  
pp. 21
Author(s):  
Abdul Ghafar ◽  
Anson V. Koehler ◽  
Ross S. Hall ◽  
Charles G. Gauci ◽  
Robin B. Gasser ◽  
...  

Protists of the genera Babesia and Theileria (piroplasms) cause some of the most prevalent and debilitating diseases for bovines worldwide. In this study, we established and used a next-generation sequencing-informatic approach to explore the composition of Babesia and Theileria populations in cattle and water buffalo in a country (Pakistan) endemic for these pathogens. We collected individual blood samples from cattle (n = 212) and water buffalo (n = 154), extracted genomic DNAs, PCR-amplified the V4 hypervariable region of 18S small subunit rRNA gene from piroplasms, sequenced amplicons using Illumina technology, and then analysed data using bioinformatic platforms. The results revealed piroplasms in 68.9% (252/366) samples, with overall occurrence being markedly higher in cattle (85.8%) than in water buffaloes (45.5%). Babesia (B.) occultans and Theileria (T.) lestoquardi-like species were recorded for the first time in Pakistan, and, overall, T. annulata was most commonly detected (65.8%) followed by B. bovis (7.1%), B. bigemina (4.4%), and T. orientalis (0.5%), with the genetic variability within B. bovis being pronounced. The occurrence and composition of piroplasm species varied markedly across different agro-ecological zones. The high detection of T. annulata in asymptomatic animals suggested a relatively high level of endemic stability of tropical theileriosis in the bovine population.


2013 ◽  
Vol 63 (Pt_3) ◽  
pp. 1149-1154 ◽  
Author(s):  
Varsha Kale ◽  
Snædís H. Björnsdóttir ◽  
Ólafur H. Friðjónsson ◽  
Sólveig K. Pétursdóttir ◽  
Sesselja Ómarsdóttir ◽  
...  

A thermophilic, aerobic, Gram-stain-negative, filamentous bacterium, strain PRI-4131T, was isolated from an intertidal hot spring in Isafjardardjup, NW Iceland. The strain grew chemo-organotrophically on various carbohydrates. The temperature range for growth was 40–65 °C (optimum 55 °C), the pH range was pH 6.5–9.0 (optimum pH 7.0) and the NaCl range was 0–3 % (w/v) (optimum 0.5 %). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain PRI-4131T represented a distinct lineage within the class Caldilineae of the phylum Chloroflexi. The highest levels of sequence similarity, about 91 %, were with Caldilinea aerophila STL-6-O1T and Caldilinea tarbellica D1-25-10-4T. Fermentative growth was not observed for strain PRI-4131T, which, in addition to other characteristics, distinguished it from the two Caldilinea species. Owing to both phylogenetic and phenotypic differences from the described members of the class Caldilineae , we propose to accommodate strain PRI-4131T in a novel species in a new genus, Litorilinea aerophila gen. nov., sp. nov. The type strain of Litorilinea aerophila is PRI-4131T ( = DSM 25763T  = ATCC BAA-2444T).


2006 ◽  
Vol 72 (10) ◽  
pp. 6452-6460 ◽  
Author(s):  
Paul J. Hunter ◽  
Geoff M. Petch ◽  
Leo A. Calvo-Bado ◽  
Tim R. Pettitt ◽  
Nick R. Parsons ◽  
...  

ABSTRACT The microbiological characteristics associated with disease-suppressive peats are unclear. We used a bioassay for Pythium sylvaticum-induced damping-off of cress seedlings to identify conducive and suppressive peats. Microbial activity in unconditioned peats was negatively correlated with the counts of P. sylvaticum at the end of the bioassay. Denaturing gradient gel electrophoresis (DGGE) profiling and clone library analyses of small-subunit rRNA gene sequences from two suppressive and two conducive peats differed in the bacterial profiles generated and the diversity of sequence populations. There were also significant differences between bacterial sequence populations from suppressive and conducive peats. The frequencies of a number of microbial groups, including the Rhizobium-Agrobacterium group (specifically sequences similar to those for the genera Ochrobactrum and Zoogloea) and the Acidobacteria, increased specifically in the suppressive peats, although no single bacterial group was associated with disease suppression. Fungal DGGE profiles varied little over the course of the bioassay; however, two bands associated specifically with suppressive samples were detected. Sequences from these bands corresponded to Basidiomycete yeast genera. Although the DGGE profiles were similar, fungal sequence diversity also increased during the bioassay. Sequences highly similar to those of Cryptococcus increased in relative abundance during the bioassay, particularly in the suppressive samples. This study highlights the importance of using complementary approaches to molecular profiling of complex populations and provides the first report that basidiomycetous yeasts may be associated with the suppression of Pythium-induced diseases in peats.


Parasitology ◽  
2008 ◽  
Vol 135 (6) ◽  
pp. 691-699 ◽  
Author(s):  
A. SAITO-ITO ◽  
N. TAKADA ◽  
F. ISHIGURO ◽  
H. FUJITA ◽  
Y. YANO ◽  
...  

SUMMARYField rodent surveys forBabesiainfection were performed from 2002 to 2005 in the vicinities of human babesiosis occurrences in Taiwan and mainland China.Babesia microtiwas identified by microscopical examination and/or PCR in 1Rattus coxingaand 1Crocidura horsfieldiiin central Taiwan and in 13Niviventer confucianusand 1Apodemus agrariusin Zhejiang and Fujian Provinces of southeastern China. Of 15B. microtisamples detected by PCR, all except 1 were shown to be the Kobe-type, the aetiological small subunit rRNA gene-type of the first Japanese patient; the exception was also a Kobe-related type. The Kobe-type had been found in rodents only in a few places including the human infection occurrence place in Japan. The internal transcribed spacer 1 to 2 sequences of the Taiwanese and Chinese Kobe-types were very similar to each other but considerably different (approx. 94% pairwise identities) from that of the Japanese Kobe-type. A Taiwanese Kobe-type strain was serologically differentiated from the Kobe strain originating from the Japanese first patient. The distribution of the Kobe-type in the vicinities of human babesiosis occurrences in Taiwan and China as well as in Japan is suggestive of involvement of the Kobe-type in Asian human babesiosis.


2017 ◽  
Vol 866 ◽  
pp. 144-147
Author(s):  
Duongruitai Nicomrat ◽  
Paisan Kanthang ◽  
Siriphatrc Chamutpong

The research was conducted to understand the diversity of microbial communities in the rice cultivars KDM 105 in the rice fields at Sanamchaikate, Chachoengsao Province. The culturing bacterial community in paddy soil before planting, during the planting and sowing of rice, and after rice collection as well as isolation of free nitrogen fixing bacteria under aerobic and anaerobic conditions were identified by molecular comparision of 16S small subunit rRNA genes as well as species diversity and their richness by Most Probable Number (MPN) method. Culturable bacterial isolates in the soil around the roots of rice varieties were determined for their physical appearances on the solid culture (Plate culturing method) and the microscopic observation under light microscope. It was found that bacteria in the paddy soil complemented with organic fertilizers and no pesticide application for over five years had a pH range from 5.2 to 5.5 cultivated jasmine rice, 8-9 log Units of free N2-fixing bacteria near the roots compared with those in other area having 4-5 log Units. Most of them were identified to be Pseudomonas sp. Microbacterium sp. Bacillus sp. Stenotrophomonas sp. and Burkholderia sp., by homology comparison of 16S rDNA gene at 98, 97, 99, 99.5, and 99%, respectively. This research revealed the recognizable complex and change in soil bacteria presented in paddy ecosystem. In any critical change of to the soil, the study of microbial diversity, compositions and their richness can be further useful for indicating proper soil management.


2003 ◽  
Vol 126 (1) ◽  
pp. 119-123 ◽  
Author(s):  
Christophe Noël ◽  
Corinne Peyronnet ◽  
Delphine Gerbod ◽  
Virginia P Edgcomb ◽  
Pilar Delgado-Viscogliosi ◽  
...  

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