Search results for "16S"
showing 10 items of 464 documents
16S rRNS gēna vairāku un divu mainīgo reģionu mikrobioma rekonstrukcijas algoritmu iegūto rezultātu salīdzināšana
2022
16S rRNS marķiergēna sekvencēšana ir viena no plašāk izmantotākajām un lētākajām mikrobioma taksonomiskā profila rekonstruēšanas metodēm. Taču, īso sekvencēšanas nolasījumu dēļ, visi gēna mainīgie reģioni nevar tikt nolasīti vienlaicīgi, bet tos nolasot atsevišķi zūd katra atsevišķā reģiona sasaiste ar pārējiem molekulas reģioniem kā arī par katru var tikt iegūts atšķirīgs datu apjoms, kas ierobežo kopējo mikrobioma kopas profilēšanas izšķirtspēju. Šajā darbā tiek aplūkota varbūtiskās rekonstrukcijas algoritma pieeja, kura izmanto vairāku 16S rRNS gēna reģionu noleases datus un maksimālās iespējamības varbūtisko algoritmu mikrobioma taksonomiskā profila rekonstrukcijai. Izmantojot Short MUl…
16S rDNA analysis for characterization of denitrifying bacteria isolated from three agricultural soils
2000
Bacteria capable of denitrification are spread among phylogenetically diverse groups. In the present investigation, molecular methods (amplified ribosomal DNA restriction analysis (ARDRA) and partial 16S rDNA gene sequencing) were used to determine the genetic diversity of culturable denitrifying soil bacteria. The purpose of this work was to study the microbial density and diversity of denitrifying communities isolated from two luvisols and a rendosol. The denitrifying bacterial density was significantly higher in the two luvisols (3x10(6) and 4x10(6) bacteria g(-1) dry soil) than in the rendosol (4x10(5) bacteria g(-1) dry soil). Denitrifying isolates from soils were grouped according to …
Erwinia piriflorinigrans sp. nov., a novel pathogen that causes necrosis of pear blossoms
2010
Eight Erwinia strains, isolated from necrotic pear blossoms in València, Spain, were compared with reference strains of Erwinia amylovora and Erwinia pyrifoliae, both of which are pathogenic to species of pear tree, and to other species of the family Enterobacteriaceae using a polyphasic approach. Phenotypic analyses clustered the novel isolates into one phenon, distinct from other species of the genus Erwinia, showing that the novel isolates constituted a homogeneous phenotypic group. Rep-PCR profiles, PCR products obtained with different pairs of primers and plasmid contents determined by restriction analysis showed differences between the novel strains and reference strains of E. amylovo…
Abundance of narG , nirS , nirK , and nosZ Genes of Denitrifying Bacteria during Primary Successions of a Glacier Foreland
2006
ABSTRACT Quantitative PCR of denitrification genes encoding the nitrate, nitrite, and nitrous oxide reductases was used to study denitrifiers across a glacier foreland. Environmental samples collected at different distances from a receding glacier contained amounts of 16S rRNA target molecules ranging from 4.9 × 10 5 to 8.9 × 10 5 copies per nanogram of DNA but smaller amounts of narG , nirK , and nosZ target molecules. Thus, numbers of narG , nirK , nirS , and nosZ copies per nanogram of DNA ranged from 2.1 × 10 3 to 2.6 × 10 4 , 7.4 × 10 2 to 1.4 × 10 3 , 2.5 × 10 2 to 6.4 × 10 3 , and 1.2 × 10 3 to 5.5 × 10 3 , respectively. The densities of 16S rRNA genes per gram of soil increased with…
Combined metabolic activity within an atrazine-mineralizing community enriched from agrochemical factory soil
2007
Abstract The main objective of this work was to characterize an atrazine-mineralizing community originating from agrochemical factory soil, especially to elucidate the catabolic pathway and individual metabolic and genetic potentials of culturable members. A stable four-member bacterial community, characterized by colony morphology and 16S rDNA sequencing, was rapidly able to mineralize atrazine to CO 2 and NH 3 . Two primary organisms were identified as Arthrobacter species (ATZ1 and ATZ2) and two secondary organisms (CA1 and CA2) belonged to the genera Ochrobactrum and Pseudomonas, respectively. PCR assessment of atrazine-degrading genetic potential of the community, revealed the presence…
Maternal Microbiota, Cortisol Concentration, and Post-Partum Weight Recovery Are Dependent on Mode of Delivery
2020
© 2020 by the authors.
Metagenomic investigation of bacteria associated with dental lesions : a cross-sectional study
2019
Background Dental caries is considered as one of the most significant global health problem over the world. Dental caries initiates from bacterial shifts within the supragingival biofilm, then a polymicrobial biofilm is formed on the surface of tooth, and finally various bacterial species aggregate in a complex-organized manner. The exploiting variability in 16S rRNA gene sequence has been considered as a cost-efficient high-throughput characterization approach in human oral microbiome investigations. The aim of this study is to characterize bacterial species associated with superficial dental biofilm, underlying carious dentine and root caries lesion by16S rRNA gene-based metagenomic analy…
Gut Microbiota Analysis Results Are Highly Dependent on the 16S rRNA Gene Target Region, Whereas the Impact of DNA Extraction Is Minor
2017
Next-generation sequencing (NGS) is currently the method of choice for analyzing gut microbiota composition. As gut microbiota composition is a potential future target for clinical diagnostics, it is of utmost importance to enhance and optimize the NGS analysis procedures. Here, we have analyzed the impact of DNA extraction and selected 16S rDNA primers on the gut microbiota NGS results. Bacterial DNA from frozen stool specimens was extracted with 5 commercially available DNA extraction kits. Special attention was paid to the semiautomated DNA extraction methods that could expedite the analysis procedure, thus being especially suitable for clinical settings. The microbial composition was an…
Meconium microbiota types dominated by lactic acid or enteric bacteria are differentially associated with maternal eczema and respiratory problems in…
2013
Background Culture-dependent methods have shown that meconium, the newborn's first intestinal discharge, is not sterile, but the diversity of bacteria present in this material needs to be further characterized by means of more sensitive molecular techniques. Objective Our aims were to characterize molecularly the meconium microbiota in term infants, to assess whether it contributes to the future microbiota of the infants' gastrointestinal tract, and to evaluate how it relates to lifestyle variables and atopy-related conditions. Methods We applied high-throughput pyrosequencing of the 16S rRNA gene to study the meconium microbiota in twenty term newborns from a Spanish birth cohort. For comp…
Metagenomic Analysis of Crohn's Disease Patients Identifies Changes in the Virome and Microbiome Related to Disease Status and Therapy, and Detects P…
2015
Background The aim of this study was to survey the bacterial and viral communities in different types of samples from patients with Crohn's disease (CD) at different stages of the disease to relate their distribution with the origin and progression of this disorder. Methods A total of 42 fecal samples and 15 biopsies from 20 patients with CD and 20 healthy control individuals were collected for bacterial 16S rRNA gene profiling and DNA/RNA virome metagenomic analysis through 454 pyrosequencing. Their composition, abundance, and diversity were analyzed, and comparisons of disease status, patient status, and sample origin were used to determine statistical differences between the groups. Resu…