scholarly journals Tannins from senescent Rhizophora mangle mangrove leaves have a distinctive effect on prokaryotic and eukaryotic communities in a Distichlis spicata salt marsh soil

2020 ◽  
Vol 96 (9) ◽  
Author(s):  
Qiu-Fang Zhang ◽  
Hendrikus J Laanbroek
Keyword(s):  
Salt Marsh ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
Condensed Tannins ◽  
18S Rrna ◽  
18S Rrna Gene ◽  
Rrna Gene ◽  
Marsh Soil ◽  
Salt Marsh Soil ◽  
The 16S Rrna Gene

ABSTRACT Due to climate warming, tannin-rich Rhizophora mangle migrates into tannin-poor salt marshes, where the tannins interfere with the biogeochemistry in the soil. Changes in biogeochemistry are likely associated with changes in microbial communities. This was studied in microcosms filled with salt marsh soil and amended with leaf powder, crude condensed tannins, purified condensed tannins (PCT), all from senescent R. mangle leaves, or with tannic acid. Size and composition of the microbial communities were determined by denaturing gradient gel electrophoresis, high-throughput sequencing and real-time PCR based on the 16S and 18S rRNA genes. Compared with the control, the 16S rRNA gene abundance was lowered by PCT, while the 18S rRNA gene abundance was enhanced by all treatments. The treatments also affected the composition of the 16S rRNA and 18S rRNA gene assemblies, but the effects on the 18S rRNA gene were greater. The composition of the 18S rRNA gene, but not of the 16S rRNA gene, was significantly correlated with the mineralization of carbon, nitrogen and phosphorus. Distinctive microbial groups emerged during the different treatments. This study revealed that migration of mangroves may affect both the prokaryotic and the eukaryotic communities in salt marsh soils, but that the effects on the eukaryotes will likely be greater.

scholarly journals Feasibility of Transferring Fluorescent In Situ Hybridization Probes to an 18S rRNA Gene Phylochip and Mapping of Signal Intensities

2008 ◽  
Vol 74 (9) ◽  
pp. 2814-2821 ◽  
Author(s):  
Katja Metfies ◽  
Linda K. Medlin
Keyword(s):  
In Situ Hybridization ◽  
Secondary Structure ◽  
16S Rrna ◽  
Fluorescent In Situ Hybridization ◽  
18S Rrna ◽  
18S Rrna Gene ◽  
Rrna Gene ◽  
Rrna Molecule ◽  
The 16S Rrna Gene

ABSTRACT DNA microarray technology offers the possibility to analyze microbial communities without cultivation, thus benefiting biodiversity studies. We developed a DNA phylochip to assess phytoplankton diversity and transferred 18S rRNA probes from dot blot or fluorescent in situ hybridization (FISH) analyses to a microarray format. Similar studies with 16S rRNA probes have been done determined that in order to achieve a signal on the microarray, the 16S rRNA molecule had to be fragmented, or PCR amplicons had to be <150 bp in length to minimize the formation of a secondary structure in the molecule so that the probe could bind to the target site. We found different results with the 18S rRNA molecule. Four out of 12 FISH probes exhibited false-negative signals on the microarray; eight exhibited strong but variable signals using full-length 18S RNA molecules. A systematic investigation of the probe's accessibility to the 18S rRNA gene was made using Prymenisum parvum as the target. Fourteen additional probes identical to this target covered the regions not tested with existing FISH probes. Probes with a binding site in the first 900 bp of the gene generated positive signals. Six out of nine probes binding in the last 900 bp of the gene produced no signal. Our results suggest that although secondary structure affected probe binding, the effect is not the same for the 18S rRNA gene and the 16S rRNA gene. For the 16S rRNA gene, the secondary structure is stronger in the first half of the molecule, whereas in the 18S rRNA gene, the last half of the molecule is critical. Probe-binding sites within 18S rRNA gene molecules are important for the probe design for DNA phylochips because signal intensity appears to be correlated with the secondary structure at the binding site in this molecule. If probes are designed from the first half of the 18S rRNA molecule, then full-length 18S rRNA molecules can be used in the hybridization on the chip, avoiding the fragmentation and the necessity for the short PCR amplicons that are associated with using the 16S rRNA molecule. Thus, the 18S rRNA molecule is a more attractive molecule for use in environmental studies where some level of quantification is desired. Target size was a minor problem, whereas for 16S rRNA molecules target size rather than probe site was important.

scholarly journals Gastrointestinal Segments Influenced Fermentation End-Products, Microbiota and Microbial Abundances in Goats

2021 ◽  
Author(s):  
Tsegay Gebremariam ◽  
Zhiliang Tan
Keyword(s):  
Fatty Acids ◽  
Microbial Community ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
18S Rrna ◽  
18S Rrna Gene ◽  
Rrna Gene ◽  
Gene Copies ◽  
End Products ◽  
The Impact

Abstract Purpose: Carbohydrate diets altered fermentation end-products and microbial community in the gastrointestinal tracts (GIT) of goats. Gastrointestinal contents used to determine the impact of carbohydrate feeds on fermentation end-products and microbial community in goats.Methodology: in the study goats were assigned to one of the two treatments corn meal (CM) or Corn gluten (CG) in a randomized block design (400 g/kg DM each). Goats were slaughtered, GIT liquids were used to determine dissolved gasses, fatty acids and microbial community.Results: Goats fed CG increased molar acetate (P < 0.05), lowered butyrate and propionate in the fore and hindgut comparing to those goats received CM. Goats received CM had higher (P < 0.05) dH2 while lowered dH2S in the fore and hindgut than those goats fed with CG treatment. The fore and hindgut had higher (P < 0.01) 16S rRNA gene copies of bacteria, protozoa, methanogens and 18S rRNA gene copies fungi than in the ileum and cecum. Goats fed CG diet had higher (P < 0.05)16S rRNA gene copies of bacteria, protozoa, methanogens, and 18S rRNA gene copies of fungi than those goats fed with CM diet. Conclusion fore and hindguts improved dissolved gasses, fatty acids and microbial community comparing with in the ileum and cecum. Goats fed CM had improved the Methanobacterials order and Methanobrevibacter genus as compared with those goats fed CG. The study suggested that hindgut segments have a reasonable contribution as foregut to methane emissions from goats.

scholarly journals Iron encrustations on filamentous algae colonized by <i>Gallionella</i>-related bacteria in a metal-polluted freshwater stream

2015 ◽  
Vol 12 (10) ◽  
pp. 7705-7737
Author(s):  
J. F. Mori ◽  
T. R. Neu ◽  
S. Lu ◽  
M. Händel ◽  
K. U. Totsche ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Green Algae ◽  
Brown Algae ◽  
18S Rrna ◽  
18S Rrna Gene ◽  
Laser Scanning Microscopy ◽  
Gene Copy ◽  
Rrna Gene ◽  
Sequencing Analysis

Abstract. Filamentous macroscopic algae were observed in slightly acidic to circumneutral (pH 5.9~6.5) metal-rich stream water that leaked out in a former uranium-mining district (Ronneburg, Germany). These algae differ in color and morphology and were encrusted with Fe-deposits. To elucidate the potential interaction with Fe(II)-oxidizing bacteria (FeOB), we collected algal samples at three time points during summer 2013 and studied the algae-bacteria-mineral compositions via confocal laser scanning microscopy (CLSM), scanning electronic microscopy, Fourier transform infrared spectra, and a 16S and 18S rRNA gene based bacterial and algae community analysis. Surprisingly, sequencing analysis of 18S rRNA gene regions of green and brown algae revealed high homologies with the yellow-green freshwater algae Tribonema (99.9~100%). CLSM imaging indicates a loss of active chloroplasts in the algae cells, which may be responsible for the change in color in Tribonema. Fe(III)-precipitates on algal cells identified as ferrihydrite and schwertmannite were associated with microbes and extracellular polymeric substances (EPS)-like glycoconjugates. While the green algae were fully encrusted with Fe-precipitates, the brown algae often exhibited discontinuous series of precipitates. This pattern was likely due to the intercalary growth of algal filaments which allowed them to avoid fatal encrustation. 16S rRNA gene targeted studies based on DNA and RNA revealed that Gallionella-related FeOB dominated the bacterial RNA and DNA communities (70–97 and 63–96%, respectively) suggesting their contribution to Fe(II) oxidation. Quantitative PCR revealed higher Gallionella-related 16S rRNA gene copy numbers on the surface of green algae compared to the brown algae. The latter harbored a higher microbial diversity, including some putative predators of algae. Lower photosynthetic activities of the brown algae lead to reduced EPS production which may have enabled predator colonization. The differences observed between green and brown algae suggest that metal-tolerant Tribonema sp. provide suitable microenvironments for microaerophilic Fe-oxidizing bacteria. However, high levels of iron orchres can be fatal to the alga.

scholarly journals Phyllobacterium loti sp. nov. isolated from nodules of Lotus corniculatus

2014 ◽  
Vol 64 (Pt_3) ◽  
pp. 781-786 ◽  
Author(s):  
Maximo Sánchez ◽  
Martha-Helena Ramírez-Bahena ◽  
Alvaro Peix ◽  
María J. Lorite ◽  
Juan Sanjuán ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Sequence Similarity ◽  
Carbon Sources ◽  
Lotus Corniculatus ◽  
Culture Conditions ◽  
Rrna Gene ◽  
Content Type ◽  
Link Type ◽  
The 16S Rrna Gene

Strain S658T was isolated from a Lotus corniculatus nodule in a soil sample obtained in Uruguay. Phylogenetic analysis of the 16S rRNA gene and atpD gene showed that this strain clustered within the genus Phyllobacterium . The closest related species was, in both cases, Phyllobacterium trifolii PETP02T with 99.8 % sequence similarity in the 16S rRNA gene and 96.1 % in the atpD gene. The 16S rRNA gene contains an insert at the beginning of the sequence that has no similarities with other inserts present in the same gene in described rhizobial species. Ubiquinone Q-10 was the only quinone detected. Strain S658T differed from its closest relatives through its growth in diverse culture conditions and in the assimilation of several carbon sources. It was not able to reproduce nodules in Lotus corniculatus. The results of DNA–DNA hybridization, phenotypic tests and fatty acid analyses confirmed that this strain should be classified as a representative of a novel species of the genus Phyllobacterium , for which the name Phyllobacterium loti sp. nov. is proposed. The type strain is S658T( = LMG 27289T = CECT 8230T).

scholarly journals 16S rRNA gene and 18S rRNA gene diversity in microbial mat communities in meltwater ponds on the McMurdo Ice Shelf, Antarctica

Polar Biology ◽  
2021 ◽  
Author(s):  
Eleanor E. Jackson ◽  
Ian Hawes ◽  
Anne D. Jungblut
Keyword(s):  
16S Rrna ◽  
18S Rrna ◽  
High Throughput Sequencing ◽  
Microbial Mats ◽  
Gene Diversity ◽  
Salinity Gradient ◽  
18S Rrna Gene ◽  
Rrna Gene ◽  
Ice Shelf ◽  
The Impact

AbstractThe undulating ice of the McMurdo Ice Shelf, Southern Victoria Land, supports one of the largest networks of ice-based, multiyear meltwater pond habitats in Antarctica, where microbial mats are abundant and contribute most of the biomass and biodiversity. We used 16S rRNA and 18S rRNA gene high-throughput sequencing to compare variance of the community structure in microbial mats within and between ponds with different salinities and pH. Proteobacteria and Cyanobacteria were the most abundant phyla, and composition at OTU level was highly specific for the meltwater ponds with strong community sorting along the salinity gradient. Our study provides the first detailed evaluation of eukaryote communities for the McMurdo Ice Shelf using the 18S rRNA gene. They were dominated by Ochrophyta, Chlorophyta and Ciliophora, consistent with previous microscopic analyses, but many OTUs belonging to less well-described heterotrophic protists from Antarctic ice shelves were also identified including Amoebozoa, Rhizaria and Labyrinthulea. Comparison of 16S and 18S rRNA gene communities showed that the Eukaryotes had lower richness and greater similarity between ponds in comparison with Bacteria and Archaea communities on the McMurdo Ice shelf. While there was a weak correlation between community dissimilarity and geographic distance, the congruity of microbial assemblages within ponds, especially for Bacteria and Archaea, implies strong habitat filtering in ice shelf meltwater pond ecosystems, especially due to salinity. These findings help to understand processes that are important in sustaining biodiversity and the impact of climate change on ice-based aquatic habitats in Antarctica.

scholarly journals Diagnosis of Fulminant Pneumonia Caused by Legionella pneumophila Serogroup 8 with the Sequence Analysis of the 16S rRNA Gene

2011 ◽  
Vol 225 (1) ◽  
pp. 65-69 ◽  
Author(s):  
Toshinori Kawanami ◽  
Kazuhiro Yatera ◽  
Kazumasa Fukuda ◽  
Kei Yamasaki ◽  
Masamizu Kunimoto ◽  
...  
Keyword(s):  
Sequence Analysis ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
Legionella Pneumophila ◽  
Rrna Gene ◽  
The 16S Rrna Gene

scholarly journals The Western Progression of Lyme Disease: Infectious and NonclonalBorrelia burgdorferi Sensu LatoPopulations in Grand Forks County, North Dakota

2014 ◽  
Vol 81 (1) ◽  
pp. 48-58 ◽  
Author(s):  
Brandee L. Stone ◽  
Nathan M. Russart ◽  
Robert A. Gaultney ◽  
Angela M. Floden ◽  
Jefferson A. Vaughan ◽  
...  
Keyword(s):  
Lyme Disease ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
North Dakota ◽  
Intergenic Spacer ◽  
Rrna Gene ◽  
Content Type ◽  
Intergenic Spacer Region ◽  
Grand Forks ◽  
The 16S Rrna Gene

ABSTRACTScant attention has been paid to Lyme disease,Borrelia burgdorferi,Ixodes scapularis, or reservoirs in eastern North Dakota despite the fact that it borders high-risk counties in Minnesota. Recent reports ofB. burgdorferiandI. scapularisin North Dakota, however, prompted a more detailed examination. Spirochetes cultured from the hearts of five rodents trapped in Grand Forks County, ND, were identified asB. burgdorferi sensu latothrough sequence analyses of the 16S rRNA gene, the 16S rRNA gene-ileTintergenic spacer region,flaB,ospA,ospC, andp66. OspC typing revealed the presence of groups A, B, E, F, L, and I. Two rodents were concurrently carrying multiple OspC types. Multilocus sequence typing suggested the eastern North Dakota strains are most closely related to those found in neighboring regions of the upper Midwest and Canada. BALB/c mice were infected withB. burgdorferiisolate M3 (OspC group B) by needle inoculation or tick bite. Tibiotarsal joints and ear pinnae were culture positive, andB. burgdorferiM3 was detected by quantitative PCR (qPCR) in the tibiotarsal joints, hearts, and ear pinnae of infected mice. Uninfected larvalI. scapularisticks were able to acquireB. burgdorferiM3 from infected mice; M3 was maintained inI. scapularisduring the molt from larva to nymph; and further, M3 was transmitted from infectedI. scapularisnymphs to naive mice, as evidenced by cultures and qPCR analyses. These results demonstrate that isolate M3 is capable of disseminated infection by both artificial and natural routes of infection. This study confirms the presence of unique (nonclonal) and infectiousB. burgdorferipopulations in eastern North Dakota.

Sign in / Sign up

Export Citation Format

Share Document