scholarly journals Natural Communities of Novel Archaea and Bacteria Growing in Cold Sulfurous Springs with a String-of-Pearls-Like Morphology

2001 ◽  
Vol 67 (5) ◽  
pp. 2336-2344 ◽  
Author(s):  
Christian Rudolph ◽  
Gerhard Wanner ◽  
Robert Huber

ABSTRACT We report the identification of novel archaea living in close association with bacteria in the cold (approximately 10°C) sulfurous marsh water of the Sippenauer Moor near Regensburg, Bavaria, Germany. These microorganisms form a characteristic, macroscopically visible structure, morphologically comparable to a string of pearls. Tiny, whitish globules (the pearls; diameter, about 0.5 to 3.0 mm) are connected to each other by thin, white-colored threads. Fluorescent in situ hybridization (FISH) studies have revealed that the outer part of the pearls is mainly composed of bacteria, with a filamentous bacterium predominating. Internally, archaeal cocci are the predominant microorganisms, with up to 107 cells estimated to be present in a single pearl. The archaea appear to be embedded in a polymer of unknown chemical composition. According to FISH and 16S rRNA gene sequence analysis, the archaea are affiliated with the euryarchaeal kingdom. The new euryarchaeal sequence represents a deep phylogenetic branch within the 16S rRNA tree and does not show extensive similarity to any cultivated archaea or to 16S rRNA gene sequences from environmental samples.

2005 ◽  
Vol 71 (10) ◽  
pp. 6308-6318 ◽  
Author(s):  
Helen A. Vrionis ◽  
Robert T. Anderson ◽  
Irene Ortiz-Bernad ◽  
Kathleen R. O'Neill ◽  
Charles T. Resch ◽  
...  

ABSTRACT The geochemistry and microbiology of a uranium-contaminated subsurface environment that had undergone two seasons of acetate addition to stimulate microbial U(VI) reduction was examined. There were distinct horizontal and vertical geochemical gradients that could be attributed in large part to the manner in which acetate was distributed in the aquifer, with more reduction of Fe(III) and sulfate occurring at greater depths and closer to the point of acetate injection. Clone libraries of 16S rRNA genes derived from sediments and groundwater indicated an enrichment of sulfate-reducing bacteria in the order Desulfobacterales in sediment and groundwater samples. These samples were collected nearest the injection gallery where microbially reducible Fe(III) oxides were highly depleted, groundwater sulfate concentrations were low, and increases in acid volatile sulfide were observed in the sediment. Further down-gradient, metal-reducing conditions were present as indicated by intermediate Fe(II)/Fe(total) ratios, lower acid volatile sulfide values, and increased abundance of 16S rRNA gene sequences belonging to the dissimilatory Fe(III)- and U(VI)-reducing family Geobacteraceae. Maximal Fe(III) and U(VI) reduction correlated with maximal recovery of Geobacteraceae 16S rRNA gene sequences in both groundwater and sediment; however, the sites at which these maxima occurred were spatially separated within the aquifer. The substantial microbial and geochemical heterogeneity at this site demonstrates that attempts should be made to deliver acetate in a more uniform manner and that closely spaced sampling intervals, horizontally and vertically, in both sediment and groundwater are necessary in order to obtain a more in-depth understanding of microbial processes and the relative contribution of attached and planktonic populations to in situ uranium bioremediation.


2008 ◽  
Vol 74 (7) ◽  
pp. 2051-2058 ◽  
Author(s):  
Yan-Ling Qiu ◽  
Satoshi Hanada ◽  
Akiyoshi Ohashi ◽  
Hideki Harada ◽  
Yoichi Kamagata ◽  
...  

ABSTRACT Phenol degradation under methanogenic conditions has long been studied, but the anaerobes responsible for the degradation reaction are still largely unknown. An anaerobe, designated strain UIT, was isolated in a pure syntrophic culture. This isolate is the first tangible, obligately anaerobic, syntrophic substrate-degrading organism capable of oxidizing phenol in association with an H2-scavenging methanogen partner. Besides phenol, it could metabolize p-cresol, 4-hydroxybenzoate, isophthalate, and benzoate. During the degradation of phenol, a small amount of 4-hydroxybenzoate (a maximum of 4 μM) and benzoate (a maximum of 11 μM) were formed as transient intermediates. When 4-hydroxybenzoate was used as the substrate, phenol (maximum, 20 μM) and benzoate (maximum, 92 μM) were detected as intermediates, which were then further degraded to acetate and methane by the coculture. No substrates were found to support the fermentative growth of strain UIT in pure culture, although 88 different substrates were tested for growth. 16S rRNA gene sequence analysis indicated that strain UIT belongs to an uncultured clone cluster (group TA) at the family (or order) level in the class Deltaproteobacteria. Syntrophorhabdus aromaticivorans gen. nov., sp. nov., is proposed for strain UIT, and the novel family Syntrophorhabdaceae fam. nov. is described. Peripheral 16S rRNA gene sequences in the databases indicated that the proposed new family Syntrophorhabdaceae is largely represented by abundant bacteria within anaerobic ecosystems mainly decomposing aromatic compounds.


2014 ◽  
Vol 64 (Pt_11) ◽  
pp. 3862-3866 ◽  
Author(s):  
Shi Peng ◽  
Dong Dan Hong ◽  
Yang Bing Xin ◽  
Li Ming Jun ◽  
Wei Ge Hong

A Gram-staining-negative, non-motile, catalase- and oxidase-positive strain, designated CCNWSP36-1T, was isolated from the nodule surface of soybean [Glycine max (L.) Merrill] cultivar Zhonghuang 13. The 16S rRNA gene sequence analysis clearly showed that the isolate represented a member of the genus Sphingobacterium . On the basis of pairwise comparisons of 16S rRNA gene sequences, strain CCNWSP36-1T showed 96.8 % similarity to Sphingobacterium nematocida CCTCC AB 2010390T and less than 95.2 % similarity to other members of the genus Sphingobacterium . Growth of strain CCNWSP36-1T occurred at 10–40 °C and at pH 5.0–9.0. The NaCl range (w/v) for growth was 0–4 %. The predominant isoprenoid quinone was MK-7. The polar lipids were phosphatidylethanolamine and several unidentified polar lipids. Sphingolipid was present. The major fatty acids were iso-C15 : 0 and summed feature 3 (comprising C16 : 1ω6c and/or C16 : 1ω7c). The G+C content of the genomic DNA was 41.1 mol%. As the physiological and biochemical characteristics of strain CCNWSP36-1T and the type strains of its closest phylogenetic neighbours showed clear differences, a novel species, Sphingobacterium yanglingense, is proposed. The type strain is CCNWSP36-1T ( = ACCC 19328T = JCM 30166T).


2003 ◽  
Vol 69 (9) ◽  
pp. 5512-5518 ◽  
Author(s):  
Brett J. Baker ◽  
Philip Hugenholtz ◽  
Scott C. Dawson ◽  
Jillian F. Banfield

ABSTRACT During a molecular phylogenetic survey of extremely acidic (pH < 1), metal-rich acid mine drainage habitats in the Richmond Mine at Iron Mountain, Calif., we detected 16S rRNA gene sequences of a novel bacterial group belonging to the order Rickettsiales in the Alphaproteobacteria. The closest known relatives of this group (92% 16S rRNA gene sequence identity) are endosymbionts of the protist Acanthamoeba. Oligonucleotide 16S rRNA probes were designed and used to observe members of this group within acidophilic protists. To improve visualization of eukaryotic populations in the acid mine drainage samples, broad-specificity probes for eukaryotes were redesigned and combined to highlight this component of the acid mine drainage community. Approximately 4% of protists in the acid mine drainage samples contained endosymbionts. Measurements of internal pH of the protists showed that their cytosol is close to neutral, indicating that the endosymbionts may be neutrophilic. The endosymbionts had a conserved 273-nucleotide intervening sequence (IVS) in variable region V1 of their 16S rRNA genes. The IVS does not match any sequence in current databases, but the predicted secondary structure forms well-defined stem loops. IVSs are uncommon in rRNA genes and appear to be confined to bacteria living in close association with eukaryotes. Based on the phylogenetic novelty of the endosymbiont sequences and initial culture-independent characterization, we propose the name “Candidatus Captivus acidiprotistae.” To our knowledge, this is the first report of an endosymbiotic relationship in an extremely acidic habitat.


2010 ◽  
Vol 60 (4) ◽  
pp. 949-952 ◽  
Author(s):  
Soo-Jin Kim ◽  
Hang-Yeon Weon ◽  
Yi-Seul Kim ◽  
Rangasamy Anandham ◽  
Seung-Hee Yoo ◽  
...  

An ivory-coloured bacterium, designated strain 5YN7-3T, was isolated from a wetland, Yongneup, Korea. Cells of the strain were aerobic, Gram-stain-negative, non-motile and short rods. 16S rRNA gene sequence analysis demonstrated that strain 5YN7-3T belongs to the order Rhizobiales of the class Alphaproteobacteria and is closely related to Kaistia soli 5YN9-8T (97.8 %), Kaistia granuli Ko04T (97.6 %) and Kaistia adipata Chj404T (97.4 %). Strain 5YN7-3T showed DNA–DNA hybridization values of 28, 22 and 35 % with K. granuli Ko04T, K. soli 5YN9-8T and K. adipata Chj404T, respectively. The major fatty acids were C18 : 1 ω7c (51.2 %), C19 : 0 cyclo ω8c (25.0 %), C18 : 0 (12.9 %) and C16 : 0 (10.8 %) (>10 % of total fatty acids). Ubiquinone-10 was the major isoprenoid quinone and the DNA G+C content was 66.5 mol%. The phenotypic characteristics in combination with 16S rRNA gene sequence analysis and DNA–DNA hybridization data clearly define strain 5YN7-3T as a novel species of the genus Kaistia, for which the name Kaistia terrae sp. nov. is proposed. The type strain is 5YN7-3T (=KACC 12910T =DSM 21341T).


2007 ◽  
Vol 57 (2) ◽  
pp. 293-296 ◽  
Author(s):  
Mitsuo Sakamoto ◽  
Maki Kitahara ◽  
Yoshimi Benno

A bacterial strain isolated from human faeces, M-165T, was characterized in terms of its phenotypic and biochemical features, cellular fatty acid profile, menaquinone profile and phylogenetic position (based on 16S rRNA gene sequence analysis). A 16S rRNA gene sequence analysis showed that the isolate was a member of the genus Parabacteroides. Strain M-165T was closely related to Parabacteroides merdae strains, showing 98 % sequence similarity. The strain was obligately anaerobic, non-pigmented, non-spore-forming, non-motile, Gram-negative, rod-shaped and was able to grow on media containing 20 % bile. Although the phenotypic characteristics of the strain M-165T were similar to those of P. merdae, the isolate could be differentiated from P. merdae by means of API 20A tests for l-arabinose and l-rhamnose fermentation. DNA–DNA hybridization experiments revealed the genomic distinctiveness of the novel strain with respect to P. merdae JCM 9497T (⩽60 % DNA–DNA relatedness). The DNA G+C content of the strain is 47.6 mol%. On the basis of these data, strain M-165T represents a novel species of the genus Parabacteroides, for which the name Parabacteroides johnsonii sp. nov. is proposed. The type strain is M-165T (=JCM 13406T=DSM 18315T).


2005 ◽  
Vol 55 (2) ◽  
pp. 763-767 ◽  
Author(s):  
Rosica Valcheva ◽  
Maher Korakli ◽  
Bernard Onno ◽  
Hervé Prévost ◽  
Iskra Ivanova ◽  
...  

Twenty morphologically different strains were chosen from French wheat sourdough isolates. Cells were Gram-positive, non-spore-forming, non-motile rods. The isolates were identified using amplified-fragment length polymorphism, randomly amplified polymorphic DNA and 16S rRNA gene sequence analysis. All isolates were members of the genus Lactobacillus. They were identified as representing Lactobacillus plantarum, Lactobacillus paralimentarius, Lactobacillus sanfranciscensis, Lactobacillus spicheri and Lactobacillus sakei. However, two isolates (LP38T and LP39) could be clearly discriminated from recognized Lactobacillus species on the basis of genotyping methods. 16S rRNA gene sequence similarity and DNA–DNA relatedness data indicate that the two strains belong to a novel Lactobacillus species, for which the name Lactobacillus hammesii is proposed. The type strain is LP38T (=DSM 16381T=CIP 108387T=TMW 1.1236T).


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