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1.
Arq. ciências saúde UNIPAR ; 25(1): 79-85, jan-abr. 2021.
Article in Portuguese | LILACS | ID: biblio-1151426

ABSTRACT

Introdução: O diagnóstico da hanseníase possui números significativos que causam preocupação à saúde pública. Os casos de resistência medicamentosa nessa doença se iniciaram em meados dos anos 60 e diante do problema, a Organização Mundial da Saúde instituiu em 1981 a poliquimioterapia, associação dos antibióticos rifampicina, dapsona e clofazimina, tratamento atual de escolha. A resistência aos fármacos na hanseníase é reportada pela literatura, desvelando um obstáculo à sua eliminação. Apresentamos nessa revisão os principais aspectos da resistência medicamentosa no tratamento para hanseníase e seus impactos. Metodologia: Revisão sistemática sobre os aspectos da resistência medicamentosa utilizando a pesquisa exploratória como metodologia de abordagem. Foram pesquisados os termos resistência medicamentosa, hanseníase, recidiva, alterações genéticas e os operadores booleanos "and" e "or" na busca. Resultados e discussão: A dificuldade de tomar a medicação corretamente foi um dos principais fatores que acarretaram resistência do bacilo Mycobacterium leprae aos fármacos. Homens de países norte e sul-americanos e asiáticos foram os mais atingidos por episódios de resistência. A resistência medicamentosa é uma das principais causas de recidivas em hanseníase. O principal fármaco causador de resistência medicamentosa descrito nos trabalhos foi a dapsona (46,6%) e a maioria das alterações genéticas encontradas estão no gene rpoB; 23,2% dos registros relatados foram de resistência secundária aos fármacos e, também, sete casos de resistência múltipla a esses medicamentos. Conclusão: Os principais aspectos da resistência medicamentosa na hanseníase são os equívocos ao ingerir os medicamentos e as alterações genéticas na bactéria. Os impactos causados estão na dificuldade de refazer o tratamento, a possibilidade de nova transmissão e o aparecimento de sintomas mais graves.


Introduction: The diagnosis of leprosy has significant numbers causing public health concern. Reports of drug resistance in this disease begun in the mid-1960s and due to this problem, the World Health Organization instituted a multidrug therapy with rifampicin, dapsone, and clofazimine antibiotic association in 1981, which is currently the first-choice treatment for leprosy. Cases of drug resistance have been reported in literature, revealing an obstacle to the eradication of the disease. This paper has the purpose of presenting the key aspects and impacts of drug resistance in the treatment for leprosy. Methods: Systematic review of the drug resistance aspects using exploratory research as an approach methodology. The authors searched the terms drug resistance, leprosy, recurrence, genetic alterations, and the Boolean operators "and" and "or" between them. Results and discussion: The difficulty in taking the medication correctly was one of the key factors that led to drug resistance for Mycobacterium leprae. Men from North and South American, as well as from Asian countries, were the most affected by episodes of resistance. Drug resistance is one of the main causes of leprosy recurrences. Dapsone was the most frequently identified drug resistance in the studies (46.6%), while most of the genetic alterations were found in the rpoB gene; 23.2% of the cases were from secondary resistance episodes, and seven cases of multiple resistance were reported. Conclusion: The misconceptions when taking the treatment and the Mycobacterium leprae genetic alterations have been described as the key aspects of drugs resistance in leprosy and the impacts caused are the difficulty in redoing the treatment, the possibility of new transmission, and the appearance of more severe symptoms.


Subject(s)
Drug Resistance/drug effects , Drug Resistance, Bacterial/drug effects , Mycobacterium leprae/drug effects , Rifampin/adverse effects , Bacteria/genetics , Pharmaceutical Preparations , Clofazimine/adverse effects , Fluoroquinolones/adverse effects , Dapsone/adverse effects , Drug Therapy, Combination/adverse effects , Leprosy/drug therapy , Anti-Bacterial Agents/adverse effects
2.
J. appl. oral sci ; 29: e20200787, 2021. tab, graf
Article in English | LILACS | ID: biblio-1250191

ABSTRACT

Abstract Objective: To define the subgingival microbial profile associated with Stage II generalized periodontitis using next-generation sequencing and to determine the relative abundance of novel periodontal pathogens and bacterial complexes. Methodology: Subgingival biofilm samples were collected from 80 subjects diagnosed with Stage II generalized periodontitis. Bacterial DNA was extracted, and 16S rRNA-based bacterial profiling via next-generation sequencing was carried out. The bacterial composition and diversity of microbial communities based on the age and sex of the patients were analyzed. The bacterial species were organized into groups: bacterial complexes (red, orange, purple, yellow, and green), novel periodontal pathogens, periodontal health-related species, and unclassified periodontal species. The results were analyzed and statistically evaluated. Results: The highest number of bacteria belonged to the phylum Bacteroidetes and Firmicutes. In terms of relative abundance, the orange complex represented 18.99%, novel bacterial species (Fretibacterium spp. and Saccharibacteria spp.) comprised 17.34%, periodontal health-related species accounted for 16.75% and unclassified periodontal species represented (Leptotrichia spp. and Selenomonas spp.) 15.61%. Novel periodontal pathogens had outweighed the periodontal disease-related red complex (5.3%). The one-sample z-test performed was statistically significant at p<0.05. The Beta diversity based on the unweighted UniFrac distance at the species level demonstrated a total variance of 15.77% based on age and 39.19% on sex, which was not statistically significant. Conclusion: The bacterial species corresponding to the disease-related orange complex and novel periodontal pathogens are predominant in Stage II generalized periodontitis.


Subject(s)
Humans , Adult , Periodontitis , Dental Plaque , Bacteria/genetics , DNA, Bacterial/genetics , RNA, Ribosomal, 16S/genetics , Prevalence , High-Throughput Nucleotide Sequencing
3.
Article in Chinese | WPRIM | ID: wpr-878956

ABSTRACT

The wild resources of Paris polyphylla var. yunnanensis, a secondary endangered medicinal plant, are severely scarce. Introduction and cultivation can alleviate market demand. To screen phosphatolytic bacteria in the rhizosphere soil of P. polyphylla var. yunnanensis and provide data support for the development of high-efficiency microbial fertilizer, in this study, the dilution plate coating method was used to isolate and screen the phosphorus solubilizing bacteria with the ability of mineralizing organic phosphorus from the rhizosphere soil of wild and transplanted varieties of P. polyphylla var. yunnanensis in 10 different locations in Yunnan, Sichuan and Guizhou. After separation and purification, the phosphatolytic capacity was analyzed by qualitative and quantitative analysis. Combined with physiological and biochemical experiments, the strains were identified using 16 S rDNA sequencing analysis. Forty one strains were selected from the rhizosphere soil of P. polyphylla var. yunnanensis from 10 different habitats. Among them, 21 strains were obtained from the rhizosphere soil of the wild variety P. polyphylla var. yunnanensis and 20 strains were obtained from the rhizosphere soil of the transplanted variety. And significance analysis found that 41 organophosphate solubilizing strains had significant differences in their ability to solubilize phosphorus. The amount of phosphate solubilizing was 0.08-67.61 mg·L~(-1), the pH value was between 4.27 and 6.82. The phosphatolytic amount of strain Y3-5 was 67.61 mg·L~(-1), and the phosphorus increase amount was 57.57 mg·L~(-1). All 41 strains were identified as Gram-positive Bacillus. Combining physiological characteristic and phylogenetic trees, Bacillus mobilis Y3-5 was finally selected as the candidate rhizosphere phosphatolytic bacteria of P. polyphylla var. yunnanensis. The distribution of phosphorus solubilizing bacteria in the rhizosphere soil of P. polyphylla var. yunnanensis was different, and there were significant diffe-rences in phosphorus solubility. Organophosphate-dissolving strain Y3-5 is expected to be a candidate strain of P. polyphylla var. yunnanensis microbial fertilizer.


Subject(s)
Bacillus , Bacteria/genetics , China , Liliaceae , Phylogeny
4.
Chinese Journal of Biotechnology ; (12): 1737-1747, 2021.
Article in Chinese | WPRIM | ID: wpr-878664

ABSTRACT

14- to 16-membered macrolide antibiotics (MA) are clinically important anti-infective drugs. With the rapid emergence of bacterial resistance, there is an urgent need to develop novel MA to counter drug-resistant bacteria. The targeted optimization of MA can be guided by analyzing the interaction between the MA and its ribosomal targets, and the desired MA derivatives can be obtained efficiently when combining with the rapidly developed metabolic engineering approaches. In the past 30 years, metabolic engineering approaches have shown great advantages in engineering the biosynthesis of MA to create new derivatives and to improve their production. These metabolic engineering approaches include modification of the structural domains of the polyketide synthase (PKS) and post-PKS modification enzymes as well as combinatorial biosynthesis. In addition, the R&D (including the evaluation of its antimicrobial activities and the optimization through metabolic engineering) of carrimycin, a new 16-membered macrolide drug, are described in details in this review.


Subject(s)
Anti-Bacterial Agents , Bacteria/genetics , Macrolides , Metabolic Engineering , Polyketide Synthases
5.
Chinese Journal of Biotechnology ; (12): 874-910, 2021.
Article in Chinese | WPRIM | ID: wpr-878602

ABSTRACT

The development and implement of microbial chassis cells can provide excellent cell factories for diverse industrial applications, which help achieve the goal of environmental protection and sustainable bioeconomy. The synthetic biology strategy of Design-Build-Test-Learn (DBTL) plays a crucial role on rational and/or semi-rational construction or modification of chassis cells to achieve the goals of "Building to Understand" and "Building for Applications". In this review, we briefly comment on the technical development of the DBTL cycle and the research progress of a few model microorganisms. We mainly focuse on non-model bacterial cell factories with potential industrial applications, which possess unique physiological and biochemical characteristics, capabilities of utilizing one-carbon compounds or of producing platform compounds efficiently. We also propose strategies for the efficient and effective construction and application of synthetic microbial cell factories securely in the synthetic biology era, which are to discover and integrate the advantages of model and non-model industrial microorganisms, to develop and deploy intelligent automated equipment for cost-effective high-throughput screening and characterization of chassis cells as well as big-data platforms for storing, retrieving, analyzing, simulating, integrating, and visualizing omics datasets at both molecular and phenotypic levels, so that we can build both high-quality digital cell models and optimized chassis cells to guide the rational design and construction of microbial cell factories for diverse industrial applications.


Subject(s)
Bacteria/genetics , Metabolic Engineering , Synthetic Biology
6.
Electron. j. biotechnol ; 43: 16-22, Jan. 2020. tab, graf
Article in English | LILACS | ID: biblio-1087512

ABSTRACT

Background: The intestinal bacterial community has an important role in maintaining human health. Dysbiosis is a key inducer of many chronic diseases including obesity and diabetes. Kunming mice are frequently used as a model of human disease and yet little is known about the bacterial microbiome resident to the gastrointestinal tract. Results: We undertook metagenomic sequencing of the luminal contents of the stomach, duodenum, jejunum, ileum, cecum, colon, and rectum of Kunming mice. Firmicutes was the dominant bacterial phylum of each intestinal tract and Lactobacillus the dominant genus. However, the bacterial composition differed among the seven intestinal tracts of Kunming mice. Compared with the small intestine, the large intestine bacterial community of Kunming mice is more stable and diverse. Conclusions: To our knowledge, ours is the first study to systematically describe the gastrointestinal bacterial composition of Kunming mice. Our findings provide a better understanding of the bacterial composition of Kunming mice and serves as a foundation for the study of precision medicine.


Subject(s)
Animals , Mice , Bacteria/isolation & purification , Gastrointestinal Tract/microbiology , Bacteria/genetics , RNA, Ribosomal, 16S , Polymerase Chain Reaction , High-Throughput Nucleotide Sequencing , Firmicutes/isolation & purification , Gastrointestinal Microbiome , Lactobacillus/isolation & purification
7.
Chinese Journal of Biotechnology ; (12): 2556-2565, 2020.
Article in Chinese | WPRIM | ID: wpr-878511

ABSTRACT

The important role of intestinal microorganisms in human health has been widely confirmed. At present, most of the studies on intestinal microorganisms are based on amplification of the V3-V4 region of bacterial 16S rRNA gene, and little attention has been paid to archaea. In this study, a primer set which can amplify 16S rRNA gene of both bacteria and archaea at the same time was used. By comparing the community changes before and after probiotics intake, it showed that this primer set is suitable for analyzing the changes of human intestinal bacteria and archaea communities. The fecal samples of volunteers were collected, and the amplification and high-throughput sequencing were carried out by using bacterial primer set (B primer) and bacterial and archaeal universal primer (AB primer); several commonly used rRNA databases were used to determine the amplification ability of the primer set to bacteria and archaea. The results showed that AB primer could display the bacterial community amplified by B primer, and could obtain the sequence of common methanogenic archaea in intestinal tract. AB primer set can analyze the bacteria and archaea in the intestinal tract at the same time by only one amplification and sequencing, which can show the structure of intestinal microbial community more comprehensively, which is suitable for the research of intestinal microorganisms.


Subject(s)
Archaea/genetics , Bacteria/genetics , DNA Primers , DNA, Bacterial , Humans , Microbiota/genetics , Phylogeny , RNA, Ribosomal, 16S/genetics
8.
Chinese Journal of Biotechnology ; (12): 2548-2555, 2020.
Article in Chinese | WPRIM | ID: wpr-878510

ABSTRACT

In recent years, 16S rRNA amplicon sequencing technology has been widely used to study human gut microbiota and to detect unknown pathogens in clinical samples. However, its resolution to bacterial population can only reach the relative abundance of genus level, and different factors affect the final bacterial profile, such as sample concentrations, PCR cycle numbers and amplification primers. In order to solve these problems, we developed a quantitative 16S rRNA amplicon sequencing method by combining random tag and internal marker method. The new methods improved the accuracy of human gut microbiota, reduced the impact of experimental operation on the results, and improved the comparability between sequencing and other molecular biological methods.


Subject(s)
Bacteria/genetics , Gastrointestinal Microbiome/genetics , High-Throughput Nucleotide Sequencing , Humans , Polymerase Chain Reaction , RNA, Ribosomal, 16S/genetics
9.
Chinese Journal of Biotechnology ; (12): 2525-2540, 2020.
Article in Chinese | WPRIM | ID: wpr-878508

ABSTRACT

Gut microbiota is closely related to human health, and its composition can give us health information. The large-scale population sampling is required on gut microbiome research; however, fresh feces samples are not easy to obtain, and rapid low-temperature freezing is difficult to achieve. With the development of technology, preservation solutions are widely used for sample collection, storage, and transport under normal temperature conditions. Preservation solutions can be used in large scale sample collection, wide geographical distribution, diverse on-site sampling conditions, heavy workload, and poor transportation conditions. In this study, five healthy volunteers were recruited. After collecting their fresh stool samples, effect of 5 different commercial preservation solutions was evaluated at room temperature. Samples in different preservation solutions after placing fresh stool samples at the 0, 1, 3, 7, 15, and 30 days were collected. All samples were tested by 16S rRNA V3-V4 high-throughput sequencing to analyze the influence of microbiome composition in different preservation solutions. The results show that different preservation solutions had distinct effects on the gut microbiome composition. Compared with the control, different preservation solutions had little effect on the amount of OUTs; preservation solutions A, B and C were closer to the control in the composition of the gut microbiota, but preservation solution D significantly changed the composition by increasing Actinobacteria and Firmicutes abundance. With the time, all solutions tended to reduce the diversity of the microbiota. Preservation solution E significantly reduced the diversity of the flora; on the 30th day, all five solutions changed the composition; the individual differences in the composition of the gut microbiome were the main factors affecting the similarity of each sample, and were derived from different stools donors. The same samples, no matter which storage solution and storage time, were directly closer to each other. Different storage solutions had different effects on the content of Gram-positive bacilli, Gram-positive cocci and Gram-negative bacteria. Storage solutions C and E reduced the abundance of Bifidobacterium, whereas storage solution D increased; except that preservation solution E relatively reduced the abundance of Lactobacillus, but the preservation solution A, B, C, and D were all closer to the control. Except for the greater difference in preservation solution D, preservation solution C was the closest to the control group on Streptococcus; preservation solution D reduced Ruminococcaceae UCG 003 than the control group. However, other preservation solutions were not much different from the control group; different preservation solutions increased the abundance of Escherichia-Shigella than the control group, and preservation solutions A and B increased the abundance of Klebsiella, but preservation solution C, D, and E were closer to the control group. Overall, preservation solution C performed better in stabilizing the composition of the gut microbiota. This study provides reference for standardized microbiome projects. Subsequent research can choose a targeted preservation solution and preservation time based on this study.


Subject(s)
Bacteria/genetics , Feces , Gastrointestinal Microbiome , Humans , RNA, Ribosomal, 16S/genetics , Specimen Handling
10.
Chinese Journal of Biotechnology ; (12): 2511-2515, 2020.
Article in Chinese | WPRIM | ID: wpr-878506

ABSTRACT

Microbes are the most important commensal organisms in humans, animals and plants, and are the major habitants in soil, sediment, water, air and other habitats. The analysis of microbiome in these habitats has become a basic research technique. As a fast developing technology in recent years, microbiome sequencing and analysis have been widely used in human health, environmental pollution control, food industry, agriculture and animal husbandry and other fields. In order to sort out and summarize the current status, development and application prospects of microbiome sequencing and analysis technologies, this special issue has prepared a collection of 16 papers in this field, that comprise sample preservation and processing, single microbe genome sequencing and analysis, and microbiome feature analysis in special habitats, microbiome related databases and algorithms, and microbiome sequencing and analysis expert consensus. It also introduced in detail the development trend of the microbiome sequencing and analysis, in order to promote the rapid development of the microbiome sequencing and analysis industry and scientific research in China, and provide necessary reference for the healthy development of related industries.


Subject(s)
Animals , Bacteria/genetics , China , High-Throughput Nucleotide Sequencing , Humans , Metagenome , Microbiota/genetics , RNA, Ribosomal, 16S
11.
Chinese Journal of Biotechnology ; (12): 2287-2297, 2020.
Article in Chinese | WPRIM | ID: wpr-878486

ABSTRACT

Overuse of antibiotics in medical care and animal husbandry has led to the development of bacterial antimicrobial resistance, causing increasingly more health concern. In addition to genetic mutations and the formation of resistance, the various stresses bacteria encountered in the natural environment trigger their stress responses, which not only protect them from these stresses, but also change their tolerance to antimicrobials. The emergence of antimicrobial tolerance will inevitably affect the physiological metabolism of bacteria. However, bacteria can restore their sensitivity to drugs by regulating their own metabolism. This article reviews recent studies on the relationship between bacterial stress responses or the physiological metabolism and antimicrobial tolerance, intending to take more effective measures to control the occurrence and spread of antimicrobial resistance.


Subject(s)
Animals , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents , Bacteria/genetics , Drug Resistance, Bacterial , Stress, Physiological
12.
Electron. j. biotechnol ; 41: 72-80, sept. 2019. ilus, tab, graf
Article in English | LILACS | ID: biblio-1087172

ABSTRACT

Background: Microbial community analysis of electronic waste (e-waste)-polluted environments is of interest to understand the effect of toxic e-waste pollutants on the soil microbial community and to evaluate novel microorganisms resisting the toxic environment. The present study aims to investigate the bacterial community structure in soils contaminated with e-waste from various sites of Loni and Mandoli (National Capital Region (NCR), India) where e-waste dumping and recycling activities are being carried out for many years. Results: Interferences to soil metagenomic DNA extraction and PCR amplification were observed because of the presence of inhibiting components derived from circuit boards. Whole-metagenome sequencing on the Illumina MiSeq platform showed that the most abundant phyla were Proteobacteria and Firmicutes. Deltaproteobacteria and Betaproteobacteria were the most common classes under Proteobacteria. Denaturing gradient gel electrophoresis (DGGE) analysis of the bacterial 16S rRNA gene showed that e-waste contamination altered the soil bacterial composition and diversity. There was a decrease in the number of predominant bacterial groups like Proteobacteria and Firmicutes but emergence of Actinobacteria in the contaminated soil samples. Conclusions: This is the first report describing the bacterial community structure of composite soil samples of ewaste-contaminated sites of Loni and Mandoli, Delhi NCR, India. The findings indicate that novel bacteria with potential bioremediating properties may be present in the e-waste-contaminated sites and hence need to be evaluated further.


Subject(s)
Soil Microbiology , Bacteria/isolation & purification , Bacteria/genetics , Electronic Waste/analysis , Soil Pollutants , Polymerase Chain Reaction , Metals, Heavy , Proteobacteria/isolation & purification , Metagenomics , Denaturing Gradient Gel Electrophoresis , Microbiota , Firmicutes/isolation & purification , India
13.
Braz. j. biol ; 79(2): 191-200, Apr.-June 2019. tab, graf
Article in English | LILACS | ID: biblio-989448

ABSTRACT

Abstract The hygienic and sanitary control in Food and Nutrition Units (FNU) is considered a standard procedure to produce adequate meals and reduce the risk of foodborne diseases and hospital infections. This study aimed to evaluate the isolation and identification of bacteria from equipment and food contact surfaces in a hospital FNU as well as to evaluate the sanitary condition. Likewise, it was analyzed the adhesion of the microorganisms on polyethylene cutting boards. The presence of aerobic mesophilic microorganisms, yeasts, molds, coagulase-positive staphylococci, coliform and fecal coliform, and Escherichia coli were analyzed on eating tables, countertop surfaces and cutting boards used for meat or vegetable handling, and equipment such as microwaves and refrigerators. The molecular identification it was done by 16S rRNA gene sequencing. The adhesion of the microorganisms (biofilm formation) on meat and vegetable cutting boards was also evaluated by scanning electron microscopy. The results showed high numbers of all microorganisms, except for E. coli , which was not observed in the samples. The molecular analysis identified species of the Enterobacteriaceae family and species of the Pseudomonadaceae family. Scanning electron microscopy analyses revealed bacterial adhesion on the cutting board surfaces. The results obtained in this study indicated that the hygienic conditions of surfaces like plastic cutting boards and equipment in this hospital FNU were inadequate. The achievement and application of standard operating procedures could positively help in the standardization of sanitary control, reducing the microbial contamination and providing a safe food to hospitalized patients.


Resumo O controle higiênico e sanitário nas Unidades de Alimentação e Nutrição (UAN) é considerado um procedimento padrão para produzir refeições adequadas e reduzir o risco de doenças transmitidas pelos alimentos e infecções hospitalares. Este estudo teve como objetivo isolar e identificar bactérias de equipamentos e superfícies de contato com alimentos em uma UAN hospitalar, bem como avaliar a condição sanitária. Do mesmo modo, analisou-se a adesão dos micro-organismos em tábuas de corte de polietileno. A presença de micro-organismos aeróbios mesófilos, leveduras, fungos, Sthapylococcus coagulase-positivos, coliformes, coliformes fecais e Escherichia coli foi analisadas na superfície de mesas do refeitório, superfícies de bancada e tábuas de corte usadas para manuseio de carne ou vegetais e, em equipamentos como micro-ondas e refrigeradores. A identificação molecular foi feita pelo sequenciamento do gene 16S rRNA. A adesão dos micro-organismos (formação de biofilmes) em tábuas de corte de carne e de vegetais também foi avaliada por microscopia eletrônica de varredura. Os resultados mostraram elevada contagem para todos os micro-organismos analisados, exceto para E. coli, a qual não foi observada nas amostras. A análise molecular identificou espécies da família Enterobacteriaceae e Pseudomonadaceae. A análise de microscopia eletrônica de varredura revelaram adesão bacteriana nas superfícies das placsa de corte. Os resultados obtidos neste estudo indicaram que as condições higiênicas das superfícies e de equipamentos nesta UAN hospitalar estavam inadequadas. A aplicação de procedimentos operacionais padrão poderia auxiliar positivamente na padronização do controle higiênico-sanitário, reduzindo a contaminação microbiana e fornecendo um alimento seguro para pacientes hospitalizados.


Subject(s)
Humans , Environmental Microbiology , Molecular Typing , Food Microbiology , Food Service, Hospital/trends , Bacteria/isolation & purification , Bacteria/classification , Bacteria/genetics , Biofilms , Fungi/isolation & purification , Fungi/classification , Fungi/genetics
14.
J. appl. oral sci ; 27: e20180635, 2019. tab, graf
Article in English | LILACS | ID: biblio-1012524

ABSTRACT

Abstract Acetaldehyde, associated with consumption of alcoholic beverages, is known to be a carcinogen and to be related to the tongue dorsum. Objective The aim of this study was to investigate the relationship between acetaldehyde concentration in mouth air and bacterial characteristics on the tongue dorsum. Methodology Thirty-nine healthy volunteers participated in the study. Acetaldehyde concentrations in mouth air were evaluated by a high-sensitivity semiconductor gas sensor. A 16S rRNA gene sequencing technique was used to compare microbiomes between two groups, focusing on the six samples with the highest acetaldehyde concentrations (HG) and the six samples with lowest acetaldehyde concentrations (LG). Results Acetaldehyde concentration increased in correlation with the increase in bacterial count (p=0.048). The number of species observed in the oral microbiome of the HG was higher than that in the oral microbiome of the LG (p=0.011). The relative abundances of Gemella sanguinis, Veillonella parvula and Neisseria flavescens in the oral microbiome of the HG were higher than those in the oral microbiome of the LG (p<0.05). Conclusion Acetaldehyde concentration in mouth air was associated with bacterial count, diversity of microbiome, and relative abundance of G. sanguinis, V. parvula, and N. flavescens.


Subject(s)
Humans , Male , Female , Adult , Young Adult , Tongue/microbiology , Microbiota , Acetaldehyde/analysis , Mouth/surgery , Reference Values , Bacteria/isolation & purification , Bacteria/genetics , Tongue/metabolism , Candida/isolation & purification , Alcohol Drinking/metabolism , RNA, Ribosomal, 16S/analysis , RNA, Ribosomal, 16S/metabolism , Smoking/metabolism , Cross-Sectional Studies , Surveys and Questionnaires , Statistics, Nonparametric , Bacterial Load , Japan , Acetaldehyde/metabolism , Mouth/metabolism
15.
Braz. j. microbiol ; 49(4): 742-748, Oct.-Dec. 2018. graf
Article in English | LILACS | ID: biblio-974296

ABSTRACT

ABSTRACT We examined microbial communities from enriched fine and retorted shale particles using sequencing of V4 variable region of 16S rRNA. High number of microbial genera was found in both enriched shale by-products that were dominate by Actinobacteria, Firmicutes and Proteobacteria, showing differences due to microbial colonization after the pyrolysis process.


Subject(s)
Bacteria/isolation & purification , Waste Products/analysis , Geologic Sediments/microbiology , Microbiota , Phylogeny , Bacteria/classification , Bacteria/genetics , Brazil , DNA, Bacterial/genetics , RNA, Ribosomal, 16S/genetics , Geologic Sediments/chemistry , Biodiversity
16.
Braz. j. microbiol ; 49(4): 714-722, Oct.-Dec. 2018. tab, graf
Article in English | LILACS | ID: biblio-974304

ABSTRACT

ABSTRACT Carnivorous plant species, such as Utricularia spp., capture and digest prey. This digestion can occur through the secretion of plant digestive enzymes and/or by bacterial digestive enzymes. To comprehend the physiological mechanisms of carnivorous plants, it is essential to understand the microbial diversity related to these plants. Therefore, in the present study, we isolated and classified bacteria from different organs of Utricularia breviscapa (stolons and utricles) and from different geographic locations (São Paulo and Mato Grosso). We were able to build the first bacterium collection for U. breviscapa and study the diversity of cultivable bacteria. The results show that U. breviscapa bacterial diversity varied according to the geographic isolation site (São Paulo and Mato Grosso) but not the analyzed organs (utricle and stolon). We reported that six genera were common to both sample sites (São Paulo and Mato Grosso). These genera have previously been reported to be beneficial to plants, as well as related to the bioremediation process, showing that these isolates present great biotechnological and agricultural potential. This is the first report of an Acidobacteria isolated from U. breviscapa. The role of these bacteria inside the plant must be further investigated in order to understand their population dynamics within the host.


Subject(s)
Bacteria/isolation & purification , Magnoliopsida/microbiology , Biodiversity , Phylogeny , Bacteria/classification , Bacteria/growth & development , Bacteria/genetics , Brazil , Floods
17.
Braz. j. microbiol ; 49(4): 757-769, Oct.-Dec. 2018. tab, graf
Article in English | LILACS | ID: biblio-974306

ABSTRACT

ABSTRACT Anthropogenic activity, such as accidental oil spills, are typical sources of urban mangrove pollution that may affect mangrove bacterial communities as well as their mobile genetic elements. To evaluate remediation strategies, we followed over the time the effects of a petroleum hydrocarbon degrading consortium inoculated on mangrove tree Avicennia schaueriana against artificial petroleum contamination in a phytoremediation greenhouse experiment. Interestingly, despite plant protection due to the inoculation, denaturing gradient gel electrophoresis of the bacterial 16S rRNA gene fragments amplified from the total community DNA indicated that the different treatments did not significantly affect the bacterial community composition. However, while the bacterial community was rather stable, pronounced shifts were observed in the abundance of bacteria carrying plasmids. A PCR-Southern blot hybridization analysis indicated an increase in the abundance of IncP-9 catabolic plasmids. Denaturing gradient gel electrophoresis of naphthalene dioxygenase (ndo) genes amplified from cDNA (RNA) indicated the dominance of a specific ndo gene in the inoculated petroleum amendment treatment. The petroleum hydrocarbon degrading consortium characterization indicated the prevalence of bacteria assigned to Pseudomonas spp., Comamonas spp. and Ochrobactrum spp. IncP-9 plasmids were detected for the first time in Comamonas sp. and Ochrobactrum spp., which is a novelty of this study.


Subject(s)
Bacteria/isolation & purification , Bacteria/metabolism , Avicennia/microbiology , Hydrocarbons/metabolism , Plasmids/genetics , Plasmids/metabolism , Soil Pollutants/analysis , Soil Pollutants/metabolism , Bacteria/classification , Bacteria/genetics , Biodegradation, Environmental , DNA, Bacterial/genetics , Petroleum/analysis , RNA, Ribosomal, 16S/genetics , Petroleum Pollution/analysis , Avicennia/metabolism , Rhizosphere
18.
Braz. j. microbiol ; 49(4): 770-776, Oct.-Dec. 2018. tab, graf
Article in English | LILACS | ID: biblio-974307

ABSTRACT

ABSTRACT Anaerobic digestion is important for the management of livestock manure with high ammonia level. Although ammonia effects on anaerobic digestion have been comprehensively studied, the molecular mechanism underlying ammonia inhibition still remains elusive. In this study, based on metatranscriptomic analysis, the transcriptional profile of microbial community in anaerobic digestion under low (1500 mg L-1) and high NH4 + (5000 mg L-1) concentrations, respectively, were revealed. The results showed that high NH4 + concentrations significantly inhibited methane production but facilitated the accumulations of volatile fatty acids. The expression of methanogenic pathway was significantly inhibited by high NH4 + concentration but most of the other pathways were not significantly affected. Furthermore, the expressions of methanogenic genes which encode acetyl-CoA decarbonylase and methyl-coenzyme M reductase were significantly inhibited by high NH4 + concentration. The inhibition of the co-expressions of the genes which encode acetyl-CoA decarbonylase was observed. Some genes involved in the pathways of aminoacyl-tRNA biosynthesis and ribosome were highly expressed under high NH4 + concentration. Consequently, the ammonia inhibition on anaerobic digestion mainly focused on methanogenic process by suppressing the expressions of genes which encode acetyl-CoA decarbonylase and methyl-coenzyme M reductase. This study improved the accuracy and depth of understanding ammonia inhibition on anaerobic digestion.


Subject(s)
Bacteria/genetics , Bacteria/metabolism , Ammonia/metabolism , Bacteria/isolation & purification , Bacteria/classification , Transcription, Genetic , Bioreactors/microbiology , Fatty Acids, Volatile/metabolism , Microbiota , Anaerobiosis , Methane/metabolism
19.
Braz. j. microbiol ; 49(3): 443-451, July-Sept. 2018. tab, graf
Article in English | LILACS | ID: biblio-951793

ABSTRACT

Abstract As a glacier retreats, barren areas are exposed, and these barren areas are ideal sites to study microbial succession. In this study, we characterized the soil culturable bacterial communities and biochemical parameters of early successional soils from a receding glacier in the Tianshan Mountains. The total number of culturable bacteria ranged from 2.19 × 105 to 1.30 × 106 CFU g-1 dw and from 9.33 × 105 to 2.53 × 106 CFU g-1 dw at 4 °C and 25 °C, respectively. The number of culturable bacteria in the soil increased at 25 °C but decreased at 4 °C along the chronosequence. The total organic carbon, total nitrogen content, and enzymatic activity were relatively low in the glacier foreland. The number of culturable bacteria isolated at 25 °C was significantly positively correlated with the TOC and TN as well as the soil urease, protease, polyphenoloxidase, sucrase, catalase, and dehydrogenase activities. We obtained 358 isolates from the glacier foreland soils that clustered into 35 groups using amplified ribosomal DNA restriction analysis. These groups are affiliated with 20 genera that belong to six taxa, namely, Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Actinobacteria, Bacteroides, and Deinococcus-Thermus, with a predominance of members of Actinobacteria and Proteobacteria in all of the samples. A redundancy analysis showed that the bacterial succession was divided into three periods, an early stage (10a), a middle stage (25-74a), and a late stage (100-130a), with the total number of culturable bacteria mainly being affected by the soil enzymatic activity, suggesting that the microbial succession correlated with the soil age along the foreland.


Subject(s)
Bacteria/isolation & purification , Ice Cover/microbiology , Ice Cover/chemistry , Phylogeny , Soil/chemistry , Soil Microbiology , Bacteria/classification , Bacteria/growth & development , Bacteria/genetics , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , RNA, Ribosomal, 16S/genetics , China , Sequence Analysis, DNA , Nitrogen/analysis , Nitrogen/metabolism
20.
Braz. j. microbiol ; 49(3): 489-502, July-Sept. 2018. tab, graf
Article in English | LILACS | ID: biblio-951803

ABSTRACT

Abstract Human activities on the Earth's surface change the landscape of natural ecosystems. Mining practices are one of the most severe human activities, drastically altering the chemical, physical and biological properties of the soil environment. Bacterial communities in soil play an important role in the maintenance of ecological relationships. This work shows bacterial diversity, metabolic repertoire and physiological behavior in five ecosystems samples with different levels of impact. These ecosystems belong to a historical area in Iron Quadrangle, Minas Gerais, Brazil, which suffered mining activities until its total depletion without recovery since today. The results revealed Proteobacteria as the most predominant phylum followed by Acidobacteria, Verrucomicrobia, Planctomycetes, and Bacteroidetes. Soils that have not undergone anthropological actions exhibit an increase ability to degrade carbon sources. The richest soil with the high diversity was found in ecosystems that have suffered anthropogenic action. Our study shows profile of diversity inferring metabolic profile, which may elucidate the mechanisms underlying changes in community structure in situ mining sites in Brazil. Our data comes from contributing to know the bacterial diversity, relationship between these bacteria and can explore strategies for natural bioremediation in mining areas or adjacent areas under regeneration process in iron mining areas.


Subject(s)
Soil Microbiology , Bacteria/isolation & purification , Biodiversity , Phylogeny , Bacteria/classification , Bacteria/genetics , Bacteria/metabolism , Brazil , Ecosystem , Mining
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