scholarly journals Bathyarchaeota Occurrence in Shallow Marine Methane-rich Sediments (Saco do Mamanguá, Rio de Janeiro, Brazil)

2020 ◽  
Author(s):  
R. G. Romano ◽  
A. G. Bendia ◽  
D. C. Franco ◽  
C. N. Signori ◽  
T. Yu ◽  
...  

ABSTRACTMethane gas (CH4) reservoirs have previously been reported in tropical marine sediments of Saco do Mamanguá ria (Rio de Janeiro, Brazil). It is known that a methane microbiome can be established in methane seeps sites; however, they are still poorly characterised. In this study, we aimed to investigate the spatial and vertical distribution of the bacterial and archaeal composition and the community structure in the sediments of Saco do Mamanguá ria. For this purpose, we collected sediment samples through 100 cm long gravity corer at three different sites and performed community analysis based on 16S rRNA gene sequencing, quantification of the methyl coenzyme M reductase-encoding gene (mcrA) and geochemical analysis, including CH4 stable isotope. Our results revealed a biogenic trend for CH4 isotopic signature and a high proportion of archaeal sequences assigned as Bathyarchaeota, with a spatial distribution throughout the inner areas of the channel and the deepest strata. OTUs classified within Bathyarchaeota and Chloroflexi (Dehalococcoidia) showed positive correlation with methane concentrations, sediment depth and oxidation-reduction potential. Due to their prevalence in the microbial community, we also performed phylogenetic analysis to understand the closeness of our Bathyarchaeota OTUs with Bathyarchaeota subgroups, and the results demonstrated a close relationship particularly with Bathy-8 and Bathy-13, which possess genes for acetogenesis and methanogenesis. Although direct relations between microbial populations and the biogenic methane emissions in Saco do Mamanguá cannot be assured, our results emphasize the importance of further investigations about the potential role of Bathyarchaeota in the carbon cycling in methane-rich tropical shallow ecosystems.

2020 ◽  
Vol 13 (11) ◽  
pp. 2319-2325
Author(s):  
Rini Widayanti ◽  
Richo Apriladi Bagas Pradana ◽  
Rony Marsyal Kunda ◽  
Suhendra Pakpahan

Background and Aim: Indonesian cuscuses are now becoming scarce because of the reduction of habitat and poaching. Further, molecular characterization of Indonesian cuscuses is still very lacking. This study aimed to determine genetic markers and phylogenetic relationships of Indonesian cuscuses based on 16S rRNA gene sequences. Materials and Methods: This study used 21 cuscuses caught from two provinces and 16 islands: 13 from Maluku and eight from Papua. Cuscus samples were taken by biopsy following ethics guidelines for animals. The genome isolation was done using gSYNC DNA Mini Kit (Geneaid Biotech Ltd., Taiwan). The 16S rRNA gene was amplified by primers (16SKUSAF and 16SKUSAR), and the polymerase chain reaction product obtained was 1875 base pair (bp). The analysis of genetic characterization and the phylogenetic relationship was performed using MEGA version X software (https://www. megasoftware.net/). Results: 16S rRNA gene sequencing attained 1598 bp for all samples. Based on the 16S rRNA nucleotide sequences, cuscuses from Papua and Maluku belong to the genus Phalanger and Spilocuscus. Phalanger spp. and Spilocuscus spp. from Papua can be distinguished from Phalanger and Spilocuscus from Maluku, except Spilocuscus from Ternate has a very close relationship with cuscus from Sentani, Papua. Conclusion: Indonesian cuscuses were derived into two clades based on 16S rRNA gene sequence, one group to genus Phalanger and another group to Spilocuscus.


RMD Open ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. e001755
Author(s):  
Maria Chiara Ditto ◽  
Simone Parisi ◽  
Gianpiero Landolfi ◽  
Richard Borrelli ◽  
Cristina Realmuto ◽  
...  

BackgroundThe close relationship between joints and gut inflammation has long been known and several data suggest that dysbiosis could link spondyloarthritis (SpA) to inflammatory bowel diseases (IBD). The introduction of biological drugs, in particular tumour necrosis factor inhibitors (TNFi), revolutionised the management of both these diseases. While the impact of conventional drugs on gut microbiota is well known, poor data are available about TNFi.AimTo investigate the impact of TNFi on gut microbiota.MethodsWe evaluated 20 patients affected by enteropathic arthritis, naïve for biological drugs, treated with TNFi at baseline and after 6 months of therapy. All patients followed a Mediterranean diet. Patients performed self-sampling of a faecal sample at baseline and after 6 months of therapy. NGS-based ITS and 16S rRNA gene sequencing was performed, followed by the taxonomic bioinformatics analysis.ResultsAfter 6 months of therapy, we detected a remarkable increase in Lachnospiraceae family (Δ +10.3, p=0.04) and Coprococcus genus (Δ +2.8, p=0.003). We also noted a decreasing trend in Proteobacteria (Δ −8.0, p=0.095) and Gammaproteobacteria (Δ −9, p=0.093) and an increasing trend in Clostridia (Δ +8.2, p=0.083). We did not find differences between TNFi responders (SpA improvement or IBD remission achieved) and non-responders in terms of alpha and beta diversity.ConclusionsOur findings are consistent with the hypothesis that TNFi therapy tends to restore the intestinal eubiosis.


2019 ◽  
Vol 13 (1) ◽  
pp. 90-101
Author(s):  
Sanju Kumari ◽  
Utkarshini Sharma ◽  
Rohit Krishna ◽  
Kanak Sinha ◽  
Santosh Kumar

Background: Cellulolysis is of considerable economic importance in laundry detergents, textile and pulp and paper industries and in fermentation of biomass into biofuels. Objective: The aim was to screen cellulase producing actinobacteria from the fruit orchard because of its requirement in several chemical reactions. Methods: Strains of actinobacteria were isolated on Sabouraud’s agar medium. Similarities in cultural and biochemical characterization by growing the strains on ISP medium and dissimilarities among them perpetuated to recognise nine groups of actinobacteria. Cellulase activity was measured by the diameter of clear zone around colonies on CMC agar and the amount of reducing sugar liberated from carboxymethyl cellulose in the supernatant of the CMC broth. Further, 16S rRNA gene sequencing and molecular characterization were placed before NCBI for obtaining recognition with accession numbers. Results: Prominent clear zones on spraying Congo Red were found around the cultures of strains of three groups SK703, SK706, SK708 on CMC agar plates. The enzyme assay for carboxymethylcellulase displayed extra cellulase activity in broth: 0.14, 0.82 and 0.66 µmol mL-1 min-1, respectively at optimum conditions of 35°C, pH 7.3 and 96 h of incubation. However, the specific cellulase activities per 1 mg of protein did not differ that way. It was 1.55, 1.71 and 1.83 μmol mL-1 min-1. The growing mycelia possessed short compact chains of 10-20 conidia on aerial branches. These morphological and biochemical characteristics, followed by their verification by Bergey’s Manual, categorically allowed the strains to be placed under actinobacteria. Further, 16S rRNA gene sequencing, molecular characterization and their evolutionary relationship through phylogenetics also confirmed the putative cellulase producing isolates of SK706 and SK708 subgroups to be the strains of Streptomyces. These strains on getting NCBI recognition were christened as Streptomyces glaucescens strain SK91L (KF527284) and Streptomyces rochei strain SK78L (KF515951), respectively. Conclusion: Conclusive evidence on the basis of different parameters established the presence of cellulase producing actinobacteria in the litchi orchard which can convert cellulose into fermentable sugar.


Life ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 254
Author(s):  
Ying Wang ◽  
Jianqing Zhu ◽  
Jie Fang ◽  
Li Shen ◽  
Shuojia Ma ◽  
...  

We characterized the gut microbial composition and relative abundance of gut bacteria in the larvae and adults of Pieris canidia by 16S rRNA gene sequencing. The gut microbiota structure was similar across the life stages and sexes. The comparative functional analysis on P. canidia bacterial communities with PICRUSt showed the enrichment of several pathways including those for energy metabolism, immune system, digestive system, xenobiotics biodegradation, transport, cell growth and death. The parameters often used as a proxy of insect fitness (development time, pupation rate, emergence rate, adult survival rate and weight of 5th instars larvae) showed a significant difference between treatment group and untreated group and point to potential fitness advantages with the gut microbiomes in P. canidia. These data provide an overall view of the bacterial community across the life stages and sexes in P. canidia.


Microbiome ◽  
2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Janis R. Bedarf ◽  
Naiara Beraza ◽  
Hassan Khazneh ◽  
Ezgi Özkurt ◽  
David Baker ◽  
...  

Abstract Background Recent studies suggested the existence of (poly-)microbial infections in human brains. These have been described either as putative pathogens linked to the neuro-inflammatory changes seen in Parkinson’s disease (PD) and Alzheimer’s disease (AD) or as a “brain microbiome” in the context of healthy patients’ brain samples. Methods Using 16S rRNA gene sequencing, we tested the hypothesis that there is a bacterial brain microbiome. We evaluated brain samples from healthy human subjects and individuals suffering from PD (olfactory bulb and pre-frontal cortex), as well as murine brains. In line with state-of-the-art recommendations, we included several negative and positive controls in our analysis and estimated total bacterial biomass by 16S rRNA gene qPCR. Results Amplicon sequencing did detect bacterial signals in both human and murine samples, but estimated bacterial biomass was extremely low in all samples. Stringent reanalyses implied bacterial signals being explained by a combination of exogenous DNA contamination (54.8%) and false positive amplification of host DNA (34.2%, off-target amplicons). Several seemingly brain-enriched microbes in our dataset turned out to be false-positive signals upon closer examination. We identified off-target amplification as a major confounding factor in low-bacterial/high-host-DNA scenarios. These amplified human or mouse DNA sequences were clustered and falsely assigned to bacterial taxa in the majority of tested amplicon sequencing pipelines. Off-target amplicons seemed to be related to the tissue’s sterility and could also be found in independent brain 16S rRNA gene sequences. Conclusions Taxonomic signals obtained from (extremely) low biomass samples by 16S rRNA gene sequencing must be scrutinized closely to exclude the possibility of off-target amplifications, amplicons that can only appear enriched in biological samples, but are sometimes assigned to bacterial taxa. Sequences must be explicitly matched against any possible background genomes present in large quantities (i.e., the host genome). Using close scrutiny in our approach, we find no evidence supporting the hypothetical presence of either a brain microbiome or a bacterial infection in PD brains.


2021 ◽  
Vol 45 (1) ◽  
Author(s):  
Musa Saheed Ibrahim ◽  
Beckley Ikhajiagbe

Abstract Background Rice forms a significant portion of food consumed in most household worldwide. Rice production has been hampered by soil factors such as ferruginousity which has limited phosphorus availability; an important mineral component for the growth and yield of rice. The presence of phosphate-solubilizing bacteria (PSB) in soils has been reported to enhance phosphate availability. In view of this, the present study employed three bacteria species (BCAC2, EMBF2 and BCAF1) that were previously isolated and proved P solubilization capacities as inocula to investigate the growth response of rice germinants in an in vitro setup. The bacteria isolates were first identified using 16S rRNA gene sequencing and then applied as inoculum. The inolula were prepared in three concentrations (10, 7.5 and 5.0 ml) following McFarland standard. Viable rice (var. FARO 44) seeds were sown in petri dishes and then inoculated with the three inocula at the different concentrations. The setup was studied for 28 days. Results 16S rRNA gene sequencing identified the isolates as: isolate BCAC2= Bacillus cereus strain GGBSU-1, isolate BCAF1= Proteus mirabilis strain TL14-1 and isolate EMBF2= Klebsiella variicola strain AUH-KAM-9. Significant improvement in rice germination, morphology, physiology and biomass parameters in the bacteria-inoculated setups was observed compared to the control. Germination percentage after 4 days was 100 % in the inoculated rice germinants compared to 65% in the control (NiS). Similarly, inoculation with the test isolates enhanced water-use efficiency by over 40%. The rice seedlings inoculated with Bacillus cereus strain GGBSU-1 (BiS) showed no signs of chlorosis and necrosis throughout the study period as against those inoculated with Proteus mirabilis strain TL14-1 (PiS) and Klebsiella variicola strain AUH-KAM-9 (KiS). Significant increase in chlorophyll-a, chlorophyll-b and alpha amylase was observed in the rice seedlings inoculated with BiS as against the NiS. Conclusion Inoculating rice seeds with Bacillus cereus strain GGBSU-1, Proteus mirabilis strain TL14-1 and Klebsiella variicola strain AUH-KAM-9 in an in vitro media significantly improved growth parameters of the test plant. Bacillus cereus strain GGBSU-1 showed higher efficiency due to a more improved growth properties observed.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Vanessa Palmas ◽  
Silvia Pisanu ◽  
Veronica Madau ◽  
Emanuela Casula ◽  
Andrea Deledda ◽  
...  

AbstractIn the present study, we characterized the distinctive signatures of the gut microbiota (GM) from overweight/obese patients (OB), and normal-weight controls (NW), both of Sardinian origin. Fecal bacterial composition of 46 OB patients (BMI = 36.6 ± 6.0; F/M = 40/6) was analyzed and compared to that of 46 NW subjects (BMI = 21.6 ± 2.1; F/M = 41/5), matched for sex, age and smoking status, by using 16S rRNA gene sequencing on MiSeq Illumina platform. The gut microbial community of OB patients exhibited a significant decrease in the relative abundance of several Bacteroidetes taxa (i.e. Flavobacteriaceae, Porphyromonadaceae, Sphingobacteriaceae, Flavobacterium, Rikenella spp., Pedobacter spp., Parabacteroides spp., Bacteroides spp.) when compared to NW; instead, several Firmicutes taxa were significantly increased in the same subjects (Lachnospiraceae, Gemellaceae, Paenibacillaceae, Streptococcaceae, Thermicanaceae, Gemella, Mitsuokella, Streptococcus, Acidaminococcus spp., Eubacterium spp., Ruminococcus spp., Megamonas spp., Streptococcus, Thermicanus, Megasphaera spp. and Veillonella spp.). Correlation analysis indicated that body fatness and waist circumference negatively correlated with Bacteroidetes taxa, while Firmicutes taxa positively correlated with body fat and negatively with muscle mass and/or physical activity level. Furthermore, the relative abundance of several bacterial taxa belonging to Enterobacteriaceae family, known to exhibit endotoxic activity, was increased in the OB group compared to NW. The results extend our knowledge on the GM profiles in Italian OB, identifying novel taxa linking obesity and intestine.


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