scholarly journals Aquatic Thermal Reservoirs of Microbial Life in a Remote and Extreme High Andean Hydrothermal System

2020 ◽  
Vol 8 (2) ◽  
pp. 208
Author(s):  
Vilma Pérez ◽  
Johanna Cortés ◽  
Francisca Marchant ◽  
Cristina Dorador ◽  
Verónica Molina ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Microbial Diversity ◽  
Hydrothermal System ◽  
Benthic Communities ◽  
Hydrothermal Systems ◽  
Rrna Gene ◽  
Clone Libraries ◽  
Bacterial Clone ◽  
Hydrothermal Ecosystem

Hydrothermal systems are ideal to understand how microbial communities cope with challenging conditions. Lirima, our study site, is a polyextreme, high-altitude, hydrothermal ecosystem located in the Chilean Andean highlands. Herein, we analyze the benthic communities of three nearby springs in a gradient of temperature (42–72 °C represented by stations P42, P53, and P72) and pH, and we characterize their microbial diversity by using bacteria 16S rRNA (V4) gene metabarcoding and 16S rRNA gene clone libraries (bacteria and archaea). Bacterial clone libraries of P42 and P53 springs showed that the community composition was mainly represented by phototrophic bacteria (Chlorobia, 3%, Cyanobacteria 3%, at P42; Chlorobia 5%, and Chloroflexi 5% at P53), Firmicutes (32% at P42 and 43% at P53) and Gammaproteobacteria (13% at P42 and 29% at P53). Furthermore, bacterial communities that were analyzed by 16S rRNA gene metabarcoding were characterized by an overall predominance of Chloroflexi in springs with lower temperatures (33% at P42), followed by Firmicutes in hotter springs (50% at P72). The archaeal diversity of P42 and P53 were represented by taxa belonging to Crenarchaeota, Diapherotrites, Nanoarchaeota, Hadesarchaeota, Thaumarchaeota, and Euryarchaeota. The microbial diversity of the Lirima hydrothermal system is represented by groups from deep branches of the tree of life, suggesting this ecosystem as a reservoir of primitive life and a key system to study the processes that shaped the evolution of the biosphere.

scholarly journals Microbial Diversity Analysis of Sediment from Nakdong River Estuary in the Republic of Korea Using 16S rRNA Gene Amplicon Sequencing

2018 ◽  
Vol 7 (14) ◽  
Author(s):  
Kyunghoi Kim
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Microbial Diversity ◽  
Large Scale ◽  
Sediment Quality ◽  
River Estuary ◽  
Republic Of Korea ◽  
Rrna Gene ◽  
Nakdong River ◽  
The Republic

Deterioration of sediment quality has been found in the Nakdong River Estuary after large-scale reclamations. Here, I report microbial diversity in sediments of Nakdong River Estuary in the Republic of Korea based on 16S rRNA gene sequencing by next-generation sequencing (NGS) techniques.

Investigation of postpartum dairy cows’ uterine microbial diversity using metagenomic pyrosequencing of the 16S rRNA gene

2012 ◽  
Vol 159 (3-4) ◽  
pp. 460-469 ◽  
Author(s):  
V.S. Machado ◽  
G. Oikonomou ◽  
M.L.S. Bicalho ◽  
W.A. Knauer ◽  
R. Gilbert ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Microbial Diversity ◽  
Dairy Cows ◽  
Rrna Gene ◽  
The 16S Rrna Gene

scholarly journals Change in Bacterial Community Structure during In Situ Biostimulation of Subsurface Sediment Cocontaminated with Uranium and Nitrate

2004 ◽  
Vol 70 (8) ◽  
pp. 4911-4920 ◽  
Author(s):  
Nadia N. North ◽  
Sherry L. Dollhopf ◽  
Lainie Petrie ◽  
Jonathan D. Istok ◽  
David L. Balkwill ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Microbial Communities ◽  
Quantitative Pcr ◽  
Rrna Gene ◽  
Gene Sequences ◽  
16S Rrna Gene Sequences ◽  
Clone Libraries ◽  
Subsurface Sediments

ABSTRACT Previous studies have demonstrated that metal-reducing microorganisms can effectively promote the precipitation and removal of uranium from contaminated groundwater. Microbial communities were stimulated in the acidic subsurface by pH neutralization and addition of an electron donor to wells. In single-well push-pull tests at a number of treated sites, nitrate, Fe(III), and uranium were extensively reduced and electron donors (glucose, ethanol) were consumed. Examination of sediment chemistry in cores sampled immediately adjacent to treated wells 3.5 months after treatment revealed that sediment pH increased substantially (by 1 to 2 pH units) while nitrate was largely depleted. A large diversity of 16S rRNA gene sequences were retrieved from subsurface sediments, including species from the α, β, δ, and γ subdivisions of the class Proteobacteria, as well as low- and high-G+C gram-positive species. Following in situ biostimulation of microbial communities within contaminated sediments, sequences related to previously cultured metal-reducing δ-Proteobacteria increased from 5% to nearly 40% of the clone libraries. Quantitative PCR revealed that Geobacter-type 16S rRNA gene sequences increased in biostimulated sediments by 1 to 2 orders of magnitude at two of the four sites tested. Evidence from the quantitative PCR analysis corroborated information obtained from 16S rRNA gene clone libraries, indicating that members of the δ-Proteobacteria subdivision, including Anaeromyxobacter dehalogenans-related and Geobacter-related sequences, are important metal-reducing organisms in acidic subsurface sediments. This study provides the first cultivation-independent analysis of the change in metal-reducing microbial communities in subsurface sediments during an in situ bioremediation experiment.

Superior resolution characterisation of microbial diversity in anaerobic digesters using full-length 16S rRNA gene amplicon sequencing

2020 ◽  
Vol 178 ◽  
pp. 115815 ◽  
Author(s):  
Theo Y.C. Lam ◽  
Ran Mei ◽  
Zhuoying Wu ◽  
Patrick K.H. Lee ◽  
Wen-Tso Liu ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Microbial Diversity ◽  
Amplicon Sequencing ◽  
Full Length ◽  
Rrna Gene ◽  
Anaerobic Digesters

Anaerostipes butyraticus sp. nov., an anaerobic, butyrate-producing bacterium from Clostridium cluster XIVa isolated from broiler chicken caecal content, and emended description of the genus Anaerostipes

2010 ◽  
Vol 60 (5) ◽  
pp. 1108-1112 ◽  
Author(s):  
Venessa Eeckhaut ◽  
Filip Van Immerseel ◽  
Frank Pasmans ◽  
Evie De Brandt ◽  
Freddy Haesebrouck ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Type Strain ◽  
Broiler Chicken ◽  
Rrna Gene ◽  
Gene Sequences ◽  
16S Rrna Gene Sequences ◽  
Caecal Content ◽  
Emended Description ◽  
Bacterial Clone

Four butyrate-producing isolates were obtained from the caecal content of a 4-week-old broiler chicken. The 16S rRNA gene sequences were determined and confirmed the close relatedness of the four isolates, which suggested that they were derived from a single bacterial clone. Phylogenetic analysis based on 16S rRNA gene sequences showed that its closest relatives were members of cluster XIVa of the Clostridium subphylum of Gram-positive bacteria and that the closest related type strain was Anaerostipes caccae L1-92T (94.5 % similarity). Similarity levels of 96–98 % with sequences from uncultured bacteria from human stool samples were observed. On the basis of morphological, biochemical and phylogenetic characteristics, this strain is assigned to a novel species in the genus Anaerostipes, for which the name Anaerostipes butyraticus sp. nov. is proposed. The type strain is 35-7T (=LMG 24724T =DSM 22094T). An emended description of the genus Anaerostipes is also provided.

Microbial Diversity in Milk of Women With Mastitis: Potential Role of Coagulase-Negative Staphylococci, Viridans Group Streptococci, and Corynebacteria

2017 ◽  
Vol 33 (2) ◽  
pp. 309-318 ◽  
Author(s):  
Pilar Mediano ◽  
Leonides Fernández ◽  
Esther Jiménez ◽  
Rebeca Arroyo ◽  
Irene Espinosa-Martos ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Microbial Diversity ◽  
Bacterial Species ◽  
Total Bacterial Count ◽  
Rrna Gene ◽  
Coagulase Negative Staphylococci ◽  
Milk Samples ◽  
Lactational Mastitis ◽  
Viridans Group Streptococci

Background: Lactational mastitis constitutes a significant cause of premature weaning. However, its etiology, linked to the presence of pathogenic microorganisms, has been scarcely reported. Research aim: The aim of this study was to describe the microbial diversity in milk samples from women suffering from lactational mastitis and to identify more accurately a collection of isolates belonging to coagulase-negative staphylococci, streptococci, and coryneform bacteria. Methods: This is a cross-sectional descriptive one-group study. A total of 5,009 isolates from 1,849 mastitis milk samples was identified by culture, biochemical, and/or molecular methods at the species or genus level. A more precise identification of a collection of 211 isolates was carried out by 16S rRNA gene sequencing. Results: Mean total bacterial count in milk samples was 4.11 log10 colony-forming units/ml, 95% confidence interval [4.08, 4.15]. Staphylococcus epidermidis was the most common species being isolated from 91.56% of the samples, whereas Staphylococcus aureus was detected in 29.74%. Streptococci and corynebacteria constituted the second (70.20%) and third (16.60%) most prevalent bacterial groups, respectively, found in this study. In contrast, Candida spp. was present in only 0.54% of the samples. Sequencing of the 16S rRNA gene revealed a high diversity of bacterial species among identified isolates. Conclusion: Many coagulase-negative staphylococci, viridans group streptococci, and corynebacteria, usually dismissed as contaminant bacteria, may play an important role as etiologic agents of mastitis. Proper diagnosis of mastitis should be established after performing microbiological testing of milk based on standardized procedures. A reliable analysis must identify the mastitis-causing pathogen(s) at the species level and its(their) concentration(s).

Methylomarinovum caldicuralii gen. nov., sp. nov., a moderately thermophilic methanotroph isolated from a shallow submarine hydrothermal system, and proposal of the family Methylothermaceae fam. nov.

2014 ◽  
Vol 64 (Pt_3) ◽  
pp. 989-999 ◽  
Author(s):  
Hisako Hirayama ◽  
Mariko Abe ◽  
Masayuki Miyazaki ◽  
Takuro Nunoura ◽  
Yasuo Furushima ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Hydrothermal System ◽  
Gene Sequence ◽  
16S Rrna Gene Sequence ◽  
Rrna Gene ◽  
Rrna Gene Sequence ◽  
Content Type ◽  
Moderately Thermophilic ◽  
Link Type

A novel methane-oxidizing bacterium, strain IT-9T, was isolated from a shallow submarine hydrothermal system occurring in a coral reef in Japan. Strain IT-9T was a Gram-negative, aerobic, motile, coccoid or oval-shaped bacterium with the distinctive intracytoplasmic membrane arrangement of a type I methanotroph. Strain IT-9T was a moderately thermophilic, obligate methanotroph that grew on methane and methanol at 30–55 °C (optimum 45–50 °C). The strain possessed the particulate methane monooxygenase (pMMO). The ribulose monophosphate pathway was operative for carbon assimilation. NaCl was required for growth within a concentration range of 1–5 % (optimum 3 %). The hao gene encoding hydroxylamine oxidoreductase (HAO) involved in nitrification was detected by a PCR experiment. The major phospholipid fatty acids were C16 : 0 and C18 : 1ω7c. The major isoprenoid quinone was Q-8. The DNA G+C content was 66.0 mol%. The 16S rRNA gene sequence of strain IT-9T was only moderately related to the sequences of members of the closest genera Methylohalobius (94.1 % similarity) and Methylothermus (91.7–91.9 % similarity); however, those sequences formed a deeply branching monophyletic group within the order Methylococcales . Phylogenies based on 16S rRNA gene sequences, deduced partial PmoA sequences and deduced partial Hao sequences and physiological and chemotaxonomic characteristics revealed that strain IT-9T represents a novel species of a new genus, for which the name Methylomarinovum caldicuralii gen. nov., sp. nov. is proposed. The type strain of Methylomarinovum caldicuralii is IT-9T ( = JCM 13666T = DSM 19749T). In addition, we propose a new family, Methylothermaceae fam. nov., in the order Methylococcales , to accommodate the genera Methylothermus , Methylohalobius and Methylomarinovum. The genera Methylothermus and Methylohalobius have been recognized as being distinct from other genera in the methane-oxidizing order Methylococcales in the class Gammaproteobacteria . These genera form a distinctive monophyletic lineage within the order on the basis of 16S rRNA gene sequence phylogeny. This seems consistent with their distinctive physiological traits; the genus Methylothermus includes the most thermophilic species, and the genus Methylohalobius includes the most halophilic species, within the order. Although these two genera include only three species at the time of writing, similar sequences of 16S rRNA genes and pmoA genes encoding pMMO have been detected in a geothermal area or deep-sea hydrothermal vent fields by studies using culture-independent techniques. This suggests that unknown methanotrophs of this lineage inhabit various extreme environments.

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