scholarly journals Karakterisasi Mikrobia Rizosfer asal Tanaman Ginseng Jawa (Talinum triangulare) berdasarkan Gen Ribosomal 16S rRNA dan 18S rRNA

2018 ◽  
Vol 3 (2) ◽  
pp. 74-81
Author(s):  
Alimuddin Ali ◽  
Herlina Rante
Keyword(s):  
16S Rrna ◽  
18S Rrna ◽  
Rhizosphere Soil ◽  
18S Rrna Gene ◽  
Biologically Active ◽  
Plate Count ◽  
Rrna Gene ◽  
Plate Count Method ◽  
Bacteria And Fungi ◽  
Talinum Triangulare

The rhizosphere is a biologically active zone of the soil around plant roots that contains soil-borne microbes including bacteria and fungi.  The microbes were isolated from rhizosphere soil roots of Java ginseng. The population of microbes was estimated by plate count method. The isolates were identified based on a great variety of morphological, and cultural characteristics. The total of rhizosphere soil microbe population were  20.91(106 cfu.g−1soils) and showed that 12 isolates of bacteria, 15 isolates of actinomycetes, and 10 isolates of fungi which were found in all of soil samples. The molecular analysis of the ribosomal genes showed that the bacterial isolate, actinomycetes and fungi were closely related to of Staphylococcus sp. DGM  (JF923460), Streptomyces avidinii (EU593640) and fungi Aspergillus niger (HQ379853), respectively. Key words: rhizosphere, Java ginseng, 16S rRNA gene, 18S rRNA gene

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 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 Isolation, screening antimicrobial activity and identification of fungi from marine sediments of the area Thanh Lan, Co To, Vietnam

2020 ◽  
Vol 16 (4) ◽  
pp. 721-728
Author(s):  
Le Thi Hong Minh ◽  
Nguyen Mai Anh ◽  
Vu Thi Quyen ◽  
Vu Thi Thu Huyen ◽  
Doan Thi Mai Huong ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Marine Environment ◽  
Marine Sediments ◽  
18S Rrna ◽  
18S Rrna Gene ◽  
Biologically Active ◽  
Rrna Gene ◽  
Bioactive Substances ◽  
Fungal Strains ◽  
Chemical Structures

Marine environment is rich in natural product resources, including marine microorganisms, especially fungi which are not only seen as a potential source of highly applicable bioactive substances but also can provide for science new chemical structures. The objective of this study is to isolate and screen fungal strains with antibacterial activity from the marine environment. Twenty five strains of fungi were isolated from marine sediments of Thanh Lan, Co To island and assessed on antibiotic activity against 7 tested microbial strains, including three Gram-negative bacteria (Escherichia coli ATCC25922, Pseudomonas aeruginosa ATCC27853, Salmonella enterica ATCC13076), three Gram-positive bacteria (Enterococcus faecalis ATCC29212, Stapphylococus aureus ATCC25923, Bacillus cereus ATCC 13245), and the yeast Candida albicans ATCC10231. The minimum inhibitory concentration (MIC) against the tested microorganisms was determined for the crude extracts obtained from the culture broths after ethyl acetate extraction and vacuum rotary evaporation. Three strains with the highest antimicrobial activity M26, M30 and M45 were capable of inhibiting 4 - 5 of the 7 tested microorganisms with MIC values from 64 to 256 μg/ml, depending on each tested strain. Morphological and phylogenetic investigations based on 18S rRNA gene sequences of the three selected strains showed that strains M26 and M30 belonged to the genus Penicillium, whereas strain M45 belonged to the genus Neurospora. The sequences of 18S rRNA gene of three strains M26, M30 and M45 were registered on GenBank database with accession numbers: MH673730, MH673731, MH673732, respectively. Research results showed that marine environment has a great potential in isolation of fungal strains for the search for antibacterial substances as well as other biologically active compounds.

Bacterial, archaeal and eukaryotic diversity in Arctic sediment as revealed by 16S rRNA and 18S rRNA gene clone libraries analysis

Polar Biology ◽  
2008 ◽  
Vol 32 (1) ◽  
pp. 93-103 ◽  
Author(s):  
Fei Tian ◽  
Yong Yu ◽  
Bo Chen ◽  
Huirong Li ◽  
Yu-Feng Yao ◽  
...  
Keyword(s):  
16S Rrna ◽  
18S Rrna ◽  
18S Rrna Gene ◽  
Gene Clone ◽  
Rrna Gene ◽  
Clone Libraries ◽  
Eukaryotic Diversity ◽  
Arctic Sediment

scholarly journals Effects of Transgenic Hybrid Aspen Overexpressing Polyphenol Oxidase on Rhizosphere Diversity

2008 ◽  
Vol 74 (17) ◽  
pp. 5340-5348 ◽  
Author(s):  
Kathryn L. Oliver ◽  
Richard C. Hamelin ◽  
William E. Hintz
Keyword(s):  
16S Rrna ◽  
Polyphenol Oxidase ◽  
18S Rrna ◽  
18S Rrna Gene ◽  
Rrna Gene ◽  
Gene Sequences ◽  
Oxidase Gene ◽  
Bacterial Gene ◽  
Gene Libraries ◽  
Cpn 60

ABSTRACT This study assessed the potential effects of transgenic aspen overexpressing a polyphenol oxidase gene on diversity in rhizosphere communities. Cultivation-independent methods were used to better delineate bacterial and fungal populations associated with transgenic and nontransgenic trees. Gene libraries for the bacterial component of the rhizosphere were established using 16S rRNA and chaperonin-60 (CPN-60) gene sequences, while the fungal community was characterized using 18S rRNA gene sequences. The 16S rRNA gene libraries were dominated by alphaproteobacterial sequences, while the CPN-60 gene libraries were dominated by members of the Bacteroidetes/Chlorobi group. In both the CPN-60 and 16S rRNA libraries, there were differences in only minor components of the bacterial community between transgenic and unmodified trees, and no significant differences in species diversity were observed. Compared to the bacterial gene libraries, greater coverage of the underlying population was achieved with the fungal 18S rRNA libraries. Members of the Zygomycota, Chytridiomycota, Ascomycota, and Basidiomycota were recovered from both libraries. The dominant groups of fungi associated with each tree type were very similar, although there were some qualitative differences in the recovery of less-abundant fungi, likely as a result of the underlying heterogeneity of the fungal population. The methods employed revealed only minor differences between the bacterial and fungal communities associated with transgenic and unmodified trees.

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.

Phylogenetic relationships of Scelimeninae genera (Orthoptera: Tetrigoidea) based on COI, 16S rRNA and 18S rRNA gene sequences

Zootaxa ◽  
2018 ◽  
Vol 4482 (2) ◽  
pp. 392
Author(s):  
YA-ZHEN CHEN ◽  
WEI-AN DENG ◽  
JIA-MIN WANG ◽  
LI-LIANG LIN ◽  
SHAN-YI ZHOU
Keyword(s):  
16S Rrna ◽  
Genetic Distance ◽  
Phylogenetic Relationships ◽  
18S Rrna ◽  
18S Rrna Gene ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Average Genetic Distance ◽  
Molecular Phylogenetic ◽  
18S Rrna Genes

Scelimeninae is an important subfamily of Tetrigoidea; however, the phylogenetic relationships within Scelimeninae are poorly understood, and its generic classification has remained unstable. In this study, the COI, 16S rRNA and 18S rRNA genes from 24 species in 9 genera within Scelimeninae were amplified and sequenced, the base composition and inter-species genetic distance of the combined sequence of COI, 16S rRNA and 18S rRNA genes were analyzed, and the molecular phylogenetic relationships were reconstructed using Maximum Likelihood (ML) and Bayesian inference (BI) methods. The results of sequence analysis showed that the total length of the combined COI, 16S rRNA and 18S rRNA gene sequence was 3507 bp, including 2345 conservative sites, 1144 variable sites and 901 parsimony-informative sites. The average A+T content was 63.5% and 78.1% in the COI, 16S rRNA sequences, respectively, indicating A+T bias. The average genetic distance between all species was 0.134, and the average genetic distance in the inner group (Scelimeninae) was 0.126. A phylogenetic tree based on the combined sequences of the COI, 16S rRNA and 18S rRNA genes showed that the phylogenetic relationships among 9 Scelimeninae genera were as follows: Criotettix + (((Zhengitettix + Hebarditettix) + (Falconius + (Scelimena + Paragavialidium))) + ((Eucriotettix + Thoradonta) + Loxilobus)). The molecular phylogenetic results generally support the morphological taxonomy; at the genus level, Criotettix, Scelimena, Paragavialidium, Thoradonta and Eucriotettix are monophyletic groups, Scelimena and Paragavialidium form sister groups, and Thoradonta and Eucriotettix also form sister groups, but the relationship between Hebarditettix and Zhengitettix needs further study. At the species level, synonyms may exist between Thoradonta spiculoba and Thoradonta transpicula and Thoradonta nodulosa and Thoradonta obtusilobata, but more studies are required to confirm this inference. 

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 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.

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