Bacterial diversity associated with subalpine fir (Abies lasiocarpa) ectomycorrhizae following wildfire and salvage-logging in central British Columbia

2002 ◽  
Vol 48 (7) ◽  
pp. 611-625 ◽  
Author(s):  
Madhukar B Khetmalas ◽  
Keith N Egger ◽  
Hugues B Massicotte ◽  
Linda E Tackaberry ◽  
M Jill Clapperton
Keyword(s):  
Bacterial Diversity ◽  
16S Rdna ◽  
Bacterial Communities ◽  
Restriction Analysis ◽  
Rrna Gene ◽  
Abies Lasiocarpa ◽  
Gram Positive ◽  
Salvage Logging ◽  
Gram Positive Bacteria ◽  
Significant Difference

To assess the effect of fire and salvage logging on the diversity of mycorrhizal–bacterial communities, bacteria associated with Cenococcum, Thelephora, Tomentella, Russulaceae, and E-strain ectomycorrhizae (ECM) of Abies lasiocarpa seedlings were characterized using two approaches. First, bacteria were isolated and characterized by Biolog©, gas chromatography fatty acid methyl ester (GC-FAME), and amplified 16S rDNA restriction analysis (ARDRA). The bacterial communities retrieved from ECM from both sites were dominated by Proteobacteria (groups gamma and beta). Pseudomonas was the most common genus isolated, followed by Variovorax, Burkholderia, and Xanthomonas. Gram-positive isolates (mostly high-G+C Gram-positive bacteria) were more frequently retrieved on the burned-salvaged site, many commonly associated with the two ascomycete ECM, Cenococcum and E-strain. Pseudomonas species were retrieved more frequently from Thelephora. Although actinomycetes were isolated from all sites, almost no actinomycetes or other Gram-positive bacteria were isolated from either Thelephora or Tomentella. Second, amplified 16S rRNA gene sequences were amplified directly from root tips and then cloned into the plasmid vector pAMP1, followed by restriction analysis. This technique distinguished more genotypes than isolates retrieved by culturing methods, but generally, results were similar in that the largest proportion of the bacteria were putatively Gram-negative; putative Gram-positive bacteria were fewer and most were from the burned–salvaged site. Direct cloning resulted in many patterns that did not match any identified isolates, suggesting that a large proportion of clones were unique or not culturable by the methods used. Analysis for both protocols showed no significant difference in bacterial diversity between the burned–salvaged and unburned sites. Key words: rhizosphere bacteria, ARDRA, 16S rDNA, Biolog©, GC-FAME.

scholarly journals Polymorphism of the Polyketide Synthase Gene phlD in Biocontrol Fluorescent Pseudomonads Producing 2,4-Diacetylphloroglucinol and Comparison of PhlD with Plant Polyketide Synthases

2001 ◽  
Vol 14 (5) ◽  
pp. 639-652 ◽  
Author(s):  
Alban Ramette ◽  
Yvan Moënne-Loccoz ◽  
Geneviève Défago
Keyword(s):  
16S Rdna ◽  
Polyketide Synthase ◽  
Restriction Analysis ◽  
Polyketide Synthases ◽  
Fluorescent Pseudomonads ◽  
Phylogenetic Groups ◽  
Gram Positive ◽  
Restriction Patterns ◽  
Gram Positive Bacteria ◽  
Rdna Sequencing

Many biocontrol fluorescent pseudomonads can protect plants from soilborne fungal pathogens through production of the antifungal secondary metabolite 2,4-diacetylphloroglucinol (Phl). One of the phl biosynthetic genes, phlD, encodes a polyketide synthase similar to plant chalcone synthases. Here, restriction analysis of phlD from 39 Phl+ biocontrol fluorescent pseudomonads yielded seven different banding patterns. The gene was sequenced in seven strains, representing the different restriction patterns. Cluster analysis of phlD restriction data or phlD sequences indicated that phlD polymorphism was high, and two main clusters were obtained when predicted PhlD sequences were compared. When the seven PhlD sequences were studied with those of other procaryotic polyketide synthases (gram-positive bacteria) and plant chalcone synthases, however, Phl+ pseudomonads, gram-positive bacteria, and plants clustered separately. Yet, sequence analysis of active site regions for PhlD and plant chalcone synthases revealed that PhlD can be considered a member of the chalcone synthase family, which may be interpreted as convergent evolution of key enzymes involved in secondary metabolism. For the 39 Phl+ pseudomonads, a relationship was found among phlD restriction patterns, phylogenetic groups defined by 16S rDNA restriction analysis (confirmed by 16S rDNA sequencing), and production levels of Phl in vitro.

scholarly journals The impact of persistent bacterial bronchitis on the pulmonary microbiome of children

2017 ◽  
Author(s):  
Leah Cuthbertson ◽  
Vanessa Craven ◽  
Lynne Bingle ◽  
William O.C.M. Cookson ◽  
Mark L. Everard ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Bacterial Diversity ◽  
Community Composition ◽  
Bacterial Communities ◽  
Microbial Community Analysis ◽  
Rrna Gene ◽  
Healthy Children ◽  
Significant Difference ◽  
The Impact

AbstractPersistent bacterial bronchitis is a leading cause of chronic wet cough in young children. This study aimed to characterise the respiratory bacterial microbiota of healthy children and to assess the impact of the changes associated with the development of persistent bacterial bronchitis.Blind, protected brushings were obtained from 20 healthy controls and 24 children with persistent bacterial bronchitis, with an additional directed sample obtained from persistent bacterial bronchitis patients. DNA was extracted, quantified using a 16S rRNA gene quantitative PCR assay prior to microbial community analysis by 16S rRNA gene sequencing.No significant difference in bacterial diversity or community composition (R2 = 0.01, P = 0.36) was observed between paired blind and non-blind brushes, showing that blind brushings are a valid means of accessing the airway microbiota. This has important implications for collecting lower respiratory samples from healthy children. A significant decrease in bacterial diversity (P < 0.001) and change in community composition (R2 = 0.08, P = 0.004) was observed between controls and patients. Bacterial communities within patients with PBB were dominated by Proteobacteria, and indicator species analysis showed that Haemophilus and Neisseria were significantly associated with the patient group. In 15 (52.9%) cases the dominant organism by sequencing was not identified by standard routine clinical culture.The bacteria present in the lungs of patients with persistent bacterial bronchitis were less diverse in terms of richness and evenness. The results validate the clinical diagnosis, and suggest that more attention to bacterial communities in children with chronic cough may lead to more rapid recognition of this condition with earlier treatment and reduction in disease burden.

Phylogenetic analysis of bacterial populations in waters of the former Texcoco Lake, Mexico

2004 ◽  
Vol 50 (12) ◽  
pp. 1049-1059 ◽  
Author(s):  
Janet Jan-Roblero ◽  
Xochitl Magos ◽  
Luis Fernández ◽  
César Hernández-Rodríguez ◽  
Sylvie Le Borgne
Keyword(s):  
16S Rdna ◽  
Bacterial Communities ◽  
Soda Lakes ◽  
Phylogenetic Analyses ◽  
Bacterial Species ◽  
Intergenic Spacer ◽  
Molecular Techniques ◽  
Preliminary Evaluation ◽  
Gram Positive ◽  
Gram Positive Bacteria

Molecular techniques were used to compare the compositions of the bacterial communities of the 2 following lagoons from the former soda Texcoco Lake, Mexico: the restored Facultativa lagoon and the Nabor Carrillo lagoon. Ribosomal intergenic spacer analysis (RISA) revealed that bacterial communities of the 2 lagoons were different and presented a relatively low diversity. Clone libraries of 16S rDNA genes were constructed, and significant phylotypes were distinguished by restriction fragment length polymorphism (RFLP). A representative clone from each phylotype was partially sequenced. Molecular identification and phylogenetic analyses based on ribosomal sequences revealed that the Facultativa lagoon harbored mainly γ- and β-Proteobacteria, low G+C Gram-positive bacteria, and several members of the Halobacteriaceae family of archaea. The Nabor Carrillo lagoon mainly included typical halophilic and alkaliphilic low G+C Gram-positive bacteria, γ-Proteobacteria, and β-Proteobacteria similar to those found in other soda lakes. Several probably noncultured new bacterial species were detected. Three strains were isolated from the Nabor Carrillo lagoon, their partial 16S rDNA sequences were obtained. On this basis, they were identified as Halomonas magadiensis (H1), Halomonas eurihalina (H2), and Staphylococcus sciuri (H3). This is the first study that uses molecular techniques to investigate potential genetic diversity in the Texcoco lakes. In this preliminary evaluation, we infer the presence of alkalophilic, halophilic, or haloalkaliphilic bacteria potentially useful for biotechnology.Key words: bacterial diversity, 16S rDNA gene, soda lakes, former soda Texcoco Lake, Mexico, alkaliphiles, halophiles, haloalkaliphiles.

scholarly journals Anti-Microbial and Remineralizing Properties of Self-Adhesive Orthodontic Resin Containing Mesoporous Bioactive Glass

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3550
Author(s):  
Aerin Choi ◽  
Kyung-Hyeon Yoo ◽  
Seog-Young Yoon ◽  
Bong-Soo Park ◽  
In-Ryoung Kim ◽  
...  
Keyword(s):  
Bond Strength ◽  
Physical Properties ◽  
Bioactive Glass ◽  
Shear Bond Strength ◽  
Antibacterial Effect ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Significant Difference ◽  
Mesoporous Bioactive Glass

Self-adhesive resins (SARs) contain adhesives, which simplify the procedures of resin application, and primers, which provide sufficient bonding ability. In this study, mesoporous bioactive glass nanoparticles (MBN) were added to a SAR to easily improve the physical properties and remineralization ability. The experimental resins comprised 1%, 3%, and 5% MBN mixed in Ortho Connect Flow (GC Corp, Tokyo, Japan). As the MBN content in the SAR increased, the microhardness increased, and a statistically significant difference was observed between the cases of 1% and 5% MBN addition. Shear bond strength increased for 1% and 3% MBN samples and decreased for 5% MBN. The addition of MBN indicated a statistically significant antibacterial effect on both gram-negative and gram-positive bacteria. The anti-demineralization experiment showed that the remineralization length increased with the MBN content of the sample. Through the above results, we found that SAR containing MBN has antibacterial and remineralization effects. Thus, by adding MBN to the SAR, we investigated the possibility of orthodontic resin development, wherein the strength is enhanced and the drawbacks of the conventional SAR addressed.

scholarly journals Pyelonephritis in Pediatric Uropathic Patients: Differences from Community-Acquired Ones and Therapeutic Protocol Considerations. A 10-Year Single-Center Retrospective Study

Children ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 436
Author(s):  
Giovanni Parente ◽  
Tommaso Gargano ◽  
Stefania Pavia ◽  
Chiara Cordola ◽  
Marzia Vastano ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Retrospective Study ◽  
Success Rate ◽  
Pediatric Population ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Significant Difference ◽  
Klebsiella Spp

Pyelonephritis (PN) represents an important cause of morbidity in the pediatric population, especially in uropathic patients. The aim of the study is to demonstrate differences between PNs of uropathic patients and PNs acquired in community in terms of uropathogens involved and antibiotic sensitivity; moreover, to identify a proper empiric therapeutic strategy. A retrospective study was conducted on antibiograms on urine cultures from PNs in vesicoureteral reflux (VUR) patients admitted to pediatric surgery department and from PNs in not VUR patients admitted to Pediatric Emergency Unit between 2010 and 2020. We recorded 58 PNs in 33 patients affected by VUR and 112 PNs in the not VUR group. The mean age of not VUR patients at the PN episode was 1.3 ± 2.6 years (range: 20 days of life–3 years), and almost all the urine cultures, 111 (99.1%), isolated Gram-negative bacteria and rarely, 1 (0.9%), Gram-positive bacteria. The Gram-negative uropathogens isolated were Escherichia coli (97%), Proteus mirabilis (2%), and Klebsiella spp. (1%). The only Gram-positive bacteria isolated was an Enterococcus faecalis. As regards the antibiograms, 96% of not VUR PNs responded to beta-lactams, 99% to aminoglycosides, and 80% to sulfonamides. For the VUR group, mean age was 3.0 years ± 3.0 years (range: 9 days of life–11 years) and mean number of episodes per patient was 2.0 ± 1.0 (range: 1–5); 83% of PNs were by Gram-negatives bacteria vs. 17% by Gram-positive: the most important Gram-negative bacteria were Pseudomonas aeruginosa (44%), Escherichia coli (27%), and Klebsiella spp. (12%), while Enterococcus spp. determined 90% of Gram-positive UTIs. Regimen ampicillin/ceftazidime (success rate: 72.0%) was compared to ampicillin/amikacin (success rate of 83.0%): no statistically significant difference was found (p = 0.09). The pathogens of PNs in uropathic patients are different from those of community-acquired PNs, and clinicians should be aware of their peculiar antibiotic susceptibility. An empiric therapy based on the association ampicillin + ceftazidime is therefore suggested.

scholarly journals Difference of Procalcitonin Levels in Gram-Positive and Gram-Negative Bacterial Sepsis Patients of Indonesia Army Central Hospital Gatot Soebroto in 2016

2022 ◽  
Vol 13 (1) ◽  
pp. 38
Author(s):  
Nindy Handayani ◽  
Soroy Lardo ◽  
Nunuk Nugrohowati
Keyword(s):  
Mean Difference ◽  
P Value ◽  
Central Hospital ◽  
Bacterial Sepsis ◽  
Gram Positive ◽  
Cross Sectional ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Significant Difference ◽  
The Mean

Introduction: Procalcitonin is known as a marker of infection and indicator for severity of infections. In sepsis, elevated procalcitonin levels in blood have a significant value that can be used as a sepsis biomarker. The aim of this study was to determine the mean difference of procalcitonin levels in Gram-positive and Gram-negative bacterial sepsis patients.Methods: This study used quantitative method with cross sectional approach. The sample of this study were bacterial sepsis patients of Indonesia Army Central Hospital Gatot Soebroto in 2016 which were divided into two groups: Gram-positive and Gram-negative bacterial sepsis patients with the number of each group was 30 samples. The data were analyzed by using independent t test.Results: This study showed that mean levels of procalcitonin in Gram-positive bacterial sepsis patients was 6.47 ng/ml and Gram-negative was 66.04 ng/ml. There was a significant difference between mean levels of procalcitonin in Gram-positive and Gram-negative bacterial sepsis patients of Indonesia Army Central Hospital Gatot Soebroto in 2016 with p value = 0.000 (p < 0.05).Conclusion: The mean difference of procalcitonin levels in Gram-negative bacterial sepsis patients were higher than Gram-positive bacterial sepsis patients, because Gram-negative bacteria have lipopolysaccharide which is a strong immunostimulator and increases TNF-α production higher than Gram-positive bacteria. 

Molecular bacterial diversity and bioburden of commercial airliner cabin air

2007 ◽  
Vol 53 (11) ◽  
pp. 1259-1271 ◽  
Author(s):  
Myron T. La Duc ◽  
Tara Stuecker ◽  
Kasthuri Venkateswaran
Keyword(s):  
Bacterial Diversity ◽  
Rrna Gene ◽  
Human Respiratory Tract ◽  
Atp Assay ◽  
Gram Positive Bacteria ◽  
Air Impingement ◽  
Culture Independent ◽  
Bacterial Enumeration ◽  
Gradual Accumulation ◽  
Opportunistic Pathogenic

Culture-independent, biomarker-targeted bacterial enumeration and identification strategies were employed to estimate total bacterial burden and diversity within the cabin air of commercial airliners. Samples from each of 4 flights on 2 commercial carriers were collected via air-impingement. The total viable microbial population ranged from below detection limits to 4.1 × 106cells/m3of air, as assessed by the ATP assay. A gradual accumulation of microbes was observed from the time of passenger boarding through mid-flight, followed by a sharp decline in bacterial abundance and viability from the initiation of descent through landing. Representatives of the α-, β-, and γ-Proteobacteria, as well as Gram-positive bacteria, were isolated in varying abundance. Neisseria meningitidis rRNA gene sequences were retrieved in great abundance from Airline A followed by Streptococcus oralis/mitis sequences. Pseudomonas synxantha sequences dominated Airline B clone libraries, followed by those of N. meningitidis and S. oralis/mitis. The cabin air samples examined herein housed low bacterial diversity and were often dominated by a particular subset of bacteria: opportunistic pathogenic inhabitants of the human respiratory tract and oral cavity.

scholarly journals Loss of bacterial diversity in the sinuses is associated with lower smell discrimination scores

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Kristi Biswas ◽  
Brett Wagner Mackenzie ◽  
Charlotte Ballauf ◽  
Julia Draf ◽  
Richard G. Douglas ◽  
...  
Keyword(s):  
Bacterial Diversity ◽  
Bacterial Communities ◽  
Gene Sequencing ◽  
16S Rrna Gene Sequencing ◽  
Olfactory Dysfunction ◽  
Rrna Gene ◽  
Olfactory Loss ◽  
Olfactory Impairment ◽  
Rrna Gene Sequencing ◽  
Normal Sense

Abstract Olfactory impairment affects ~ 20% of the population and has been linked to various serious disorders. Microbes in the nasal cavity play a key role in priming the physiology of the olfactory epithelium and maintaining a normal sense of smell by the host. The aim of this study was to explore the link between olfactory dysfunction and nasal bacterial communities. A total of 162 subjects were recruited for this study from a specialized olfactory dysfunction clinic and placed into one of three groups: anosmia, hyposmia or normosmia. Swabs from the nasal middle meatus were collected from each subject then processed for bacterial 16S rRNA gene sequencing. No overall differences in bacterial diversity or composition were observed between the three cohorts in this study. However, the relative abundances of Corynebacterium spp. and Streptococcus spp. were significantly (p < 0.05) different in subjects with olfactory loss. Furthermore, subjects with deficiencies in discriminating between smells (based on discrimination scores) had a lower bacterial diversity (Simpson’s evenness p < 0.05). While these results are preliminary in nature, potential bacterial biomarkers for olfactory loss were identified. These findings need to be further validated and biologically tested in animal models.

Molecular bacterial diversity and distribution in waste from a steel plant

2008 ◽  
Vol 54 (12) ◽  
pp. 996-1005 ◽  
Author(s):  
Dulcecleide B. Freitas ◽  
Mariana P. Reis ◽  
Leandro M. Freitas ◽  
Paulo S. Assis ◽  
Edmar Chartone-Souza ◽  
...  
Keyword(s):  
Bacterial Diversity ◽  
16S Rdna ◽  
Bacterial Communities ◽  
Sequence Similarity ◽  
Diversity Indices ◽  
Operational Taxonomic Units ◽  
Rdna Sequences ◽  
Partial Length ◽  
16S Rdna Sequences ◽  
Novel Taxa

We characterized the bacterial diversity of newly produced steelmaking wastes (NPSW) and steelmaking wastes deposited (SWD) in a restricted land area, generated by the siderurgic industry, using the 16S rDNA clone library approach. A total of 212 partial-length sequences were analyzed, revealing 123 distinct operational taxonomic units (OTUs) determined by the DOTUR program to 97% sequence similarity. Phylogenetic analysis of bacterial 16S rDNA sequences from the NPSW and SWD libraries demonstrated that Gammaproteobacteria, Betaproteobacteria, Alphaproteobacteria, Actinobacteria, Planctomycetes, Firmicutes, and Bacteroidetes were represented in both libraries. Deltaproteobacteria, Acidobacteria, Chloroflexi, Deinococcus-thermus, Gemmatimonadetes, and candidate divisions OP10 and OD1 were only present in the SWD library, and Nitrospira was only present in the NPSW library. The abundance of sequences affiliated with Gammaproteobacteria was high in both libraries. Six previously unclassified OTUs may represent novel taxa. Based on diversity indices (Simpson, Shannon–Weaver, Chao1, and ACE), the SWD library had a higher diversity. LIBSHUFF comparisons of the composition of the 2 libraries showed that they were significantly different. These results indicate that the bacterial communities in steelmaking wastes present high phylogenetic diversity and complexity. A possible association between the functional diversity and the bacterial communities’ complexity requires further phenotypic investigation.

Assessment of bacterial diversity in selected Philippine fermented food products through PCR-DGGE

2011 ◽  
Vol 2 (4) ◽  
pp. 273-281 ◽  
Author(s):  
L.M. Dalmacio ◽  
A.K. Angeles ◽  
L.L. Larcia ◽  
M. Balolong ◽  
R. Estacio
Keyword(s):  
Bacterial Diversity ◽  
16S Rdna ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Acetic Acid Bacteria ◽  
Food Samples ◽  
Fermented Food ◽  
Probiotic Bacteria ◽  
Rrna Gene ◽  
Fermented Foods ◽  
16S Rdna Pcr

The bacterial population in several Philippine fermented food preparations was assessed by PCR-denaturing gradient gel electrophoresis (PCR-DGGE) of the 16S rRNA gene (16S rDNA). Genomic DNA was isolated directly from alamang (fermented shrimp paste), burong isda (fermented fish and rice), burong hipon (fermented shrimp and rice), burong mustasa (fermented mustard leaves), tuba (sugar cane wine), suka (vinegar) and sinamak (spiced vinegar) using one of two protocols, namely – MoBio DNA Extraction Kit procedure and a cetyltrimethylammonium bromide-based method. Samples recalcitrant to both methods underwent enrichment in three culture broths prior to DNA isolation. Isolated DNA was amplified using nested primer pairs targeting the bacterial 16S rDNA. PCR products were subjected to DGGE to elucidate the bacterial diversity in each fermented food. 16S rDNA sequence analyses revealed that lactic acid bacteria (LAB) and acetic acid bacteria (AAB) were dominant in the food samples. The LAB identified were Lactobacillus fermentum, Lactobacillus plantarum, Lactobacillus panis, Lactobacillus pontis and Weissella cibaria. Identified AAB were Acetobacter pomorum, Acetobacter ghanensis, Acetobacter orientalis, and Acetobacter pasteurianus. Among these, L. fermentum, L. plantarum and W. cibaria are established probiotic bacteria, while L. panis and L. pontis are potential probiotic bacteria. This finding would increase the appeal and significance of local fermented foods to consumers. Furthermore, the majority of the identified bacteria in the study have not been reported before in culture-dependent studies of similar food preparations. As such, some of the bacterial 16S rDNA obtained were cloned to have an initial partial bacterial 16S rDNA library for Philippine fermented foods.

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