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1.
Int J Syst Evol Microbiol ; 69(9): 2735-2738, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31483242

RESUMO

Early characterization of strains designated into the genera Entomoplasma and Mesoplasma was based upon biological and chemical characteristics. With the advent of 16S rRNA gene sequence analysis as an added taxonomic character, it became clear that the two genera did not form distinct and separate monophyletic clusters. A genome-level analysis of all 17 validly published species within the family Entomoplasmataceae has recently been performed. Phylogenetic analyses, comparisons of gene content, and the lack of genus-specific genes supported that species from the two genera are intermixed and should not be taxonomically separated. This level of analysis clearly reveals the necessity to revise the taxonomy of this family by merging the two genera into one, Entomoplasma. Additionally, it was definitively determined that the strain originally designated as Acholeplasma multilocale resides in this cluster and should be formally renamed as Entomoplasma multilocale. Merging Mesoplasma and Entomoplasma yields a paraphyletic genus, but is supported by cell morphology and ecology to be distinguished from the genera Spiroplasma and Mycoplasma.


Assuntos
Entomoplasmataceae/classificação , Genoma Bacteriano , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
2.
Medicine (Baltimore) ; 98(35): e16626, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31464899

RESUMO

Gastric cancer (GC) is one of the common malignant tumors in China, with a high morbidity and mortality. With the development and application of high-throughput sequencing technologies and metagenomics, a great quantity of studies have shown that gastrointestinal microbiota is closely related to digestive system diseases. Although some studies have reported the effect of long-term follow-up after subtotal gastrectomy on intestinal flora changes in patients with GC. However, the features of gut microbiota and their shifts in patients with GC in perioperative period remain unclear.This study was designed to characterize fecal microbiota shifts of the patients with GC before and after the radical distal gastrectomy (RDG) during their hospital staying periods. Furthermore, fecal microbiota was also compared between the GC patients and healthy individuals.Patients who were diagnosed with advanced gastric adenocarcinoma at distal stomach were enrolled in the study. The bacterial burden within fecal samples was determined using quantitative polymerase chain reaction. To analyze the diversity and composition of gut microbiota from fecal DNA of 20 GC patients and 22 healthy controls, amplicons of the 16S rRNA gene from all subjects were pyrosequenced. To study gut microbiota shifts, the fecal microbiota from 6 GC patients before and after RDG was detected and subsequently analyzed. Short-chain fatty acids were also detected by chromatography spectrometer in these 6 GC patients.RDG had a moderate effect on bacterial richness and evenness, but had pronounced effects on the composition of postoperative gut microbiota compared with preoperative group. The relative abundances of genera Akkermansia, Esherichia/Shigella, Lactobacillus, and Dialister were significant changed in perioperative period. Remarkably, higher abundances of Escherichia/Shigella, Veillonella, and Clostridium XVIII and lower abundances of Bacteroides were observed in gut microbiota of overall GC patients compared to healthy controls.This study is the first study to characterize the altered gut microbiota within fecal samples from GC patients during perioperative period, and provide a new insights on such microbial perturbations as a potential effector of perioperative period phenotype. Further research must validate these discoveries and may evaluate targeted microbiota shifts to improve outcomes in GC patients.


Assuntos
Bactérias/classificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA/métodos , Neoplasias Gástricas/cirurgia , Adulto , Bactérias/genética , Bactérias/isolamento & purificação , China , DNA Bacteriano/genética , DNA Ribossômico/genética , Feminino , Gastrectomia , Microbioma Gastrointestinal , Humanos , Masculino , Pessoa de Meia-Idade , Período Perioperatório , Filogenia , Neoplasias Gástricas/microbiologia
3.
J Med Microbiol ; 68(9): 1287-1291, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31364966

RESUMO

The molecular mechanism of Helicobacter pylori resistance to tetracycline involves mutations in the primary binding site of the ribosome. A resistance or reduced susceptibility to tetracycline could be the result of single, double or triple mutations in the 16S rRNA gene of H. pylori. We investigated if the genotype was correlated to tetracycline resistance as determined phenotypically in vitro for 96 H. pylori isolates in the gastroesophageal mucosa of Venezuelan individual hosts. E-test for antimicrobial susceptibility test and real-time PCR for the detection of 16S rRNA gene mutations were performed in 96 H. pylori isolates (48 obtained from antrum, and 48 from oesophagus) from eight dyspeptic patients. In the gastric mucosa, 38 isolates were identified sensitive and 10 resistant to tetracycline by E-test, whereas 44 sensitive and 4 resistant isolates were found in the oesophagus. Real-time PCR detection of the 16S rRNA gene exhibited mutants with a single base-pair substitution (AGA926GGA) in six antrum isolates and seven oesophagus isolates, whereas only three harboured a low level of tetracycline resistance in vitro. Our results indicate that real-time PCR detection of 16S rRNA is a reliable method to classify among tetracycline-resistant genotypes and useful in patients who have experienced a first-line treatment failure with triple therapy.


Assuntos
Infecções por Helicobacter/microbiologia , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/genética , RNA Ribossômico 16S/genética , Resistência a Tetraciclina/genética , Tetraciclina/farmacologia , Antibacterianos/farmacologia , Mucosa Esofágica/microbiologia , Mucosa Gástrica/microbiologia , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Mutação , Reação em Cadeia da Polimerase em Tempo Real
4.
Naturwissenschaften ; 106(9-10): 51, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31455975

RESUMO

Endophytic actinomycetes, a prolific source of natural products, are well known for their diverse metabolic versatility, and their association with medicinal plants and antimicrobial potential are well worth exploring. We isolated and identified the Streptomyces cavourensis strain MH16 inhabiting the tree Millingtonia hortensis Linn. using phylogenetic analysis based on a 16S rRNA molecular approach. We used the disc diffusion method to evaluate the impact of differences in the compositions of the media on the production of secondary metabolites from strain MH16. The production of antimicrobial metabolites was determined by the observation of inhibition zones on intensive bands when using a TLC-bioautography assay. Biosynthesis of secondary metabolites was optimal when the strain MH16 was cultured in ISP-2 medium as depicted by a zone of inhibition. Strain MH16 effectively inhibited methicillin-resistant Staphylococcus aureus, Escherichia coli, Candida albicans, and other multi drug-resistant pathogens. The minimum inhibitory concentration of the antimicrobial metabolites was 25-100 µg mL-1. The study manifests the optimization and utilization of different fermentation media which best suits for increased production of the secondary metabolites from Streptomyces cavourensis. This research suggests that the antimicrobial metabolites of strain MH16 found in M. hortensis has great potential for the biodiscovery of new anti-infective drugs against a wide range of multidrug-resistant pathogens.


Assuntos
Peptídeos Catiônicos Antimicrobianos/biossíntese , Peptídeos Catiônicos Antimicrobianos/farmacologia , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Streptomyces/genética , Streptomyces/metabolismo , Bactérias/efeitos dos fármacos , Meios de Cultura/farmacologia , Fungos/efeitos dos fármacos , Lamiales/microbiologia , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S/genética , Streptomyces/efeitos dos fármacos , Streptomyces/crescimento & desenvolvimento
5.
J Microbiol ; 57(9): 759-768, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31376108

RESUMO

The cultivation of microbial species remains a primary challenge in microbiology and obtaining pure cultures is essential for the study of microbial physiology and function. When isolating microorganisms from aquaculture environments, Vibrio are the most dominate isolates on the media that are commonly used. In order to expand our ability to study microbial species, an easy-operation and low-cost medium that can reduce the interference of Vibrio strains and increase the cultivability of other bacteria is urgently needed. We compared viable cell counts on conventional media (CM; including Marine Agar 2216 and LB media) and diluted media (DM; including 1/10-Marine Agar 2216, 1/10-LB). We also assessed the diversity of cultivable microorganisms under high and low nutrient conditions by a plate-wash strategy coupled with high-throughput sequencing of the V4 hypervariable region of the 16S rRNA gene. The results show that microbial communities from DM, especially 1/10-Marine Agar 2216, are more diverse than those obtained from CM. Vibrio isolates were reduced on DM. PICRUSt analysis revealed that nutrient composition is a significant contributor to the diversity and function of the cultivable microbial communities. Bacteria grown on CM possess more pathogenic characteristics, whereas DM favors the growth of bacteria that have multiple metabolic functions. Collectively, our data provide strong evidence that dilution of CM influences the cultivability of bacteria from aquaculture seawater. It also supports that DM can expand the range of microbial species that can be cultivated. This study also provides insights for media design in microbial cultivation from aquaculture systems.


Assuntos
Meios de Cultura/metabolismo , Água do Mar/microbiologia , Vibrio/crescimento & desenvolvimento , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Meios de Cultura/química , DNA Bacteriano/genética , Filogenia , RNA Ribossômico 16S/genética , Vibrio/genética , Vibrio/isolamento & purificação , Vibrio/metabolismo
6.
World J Microbiol Biotechnol ; 35(9): 132, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31432260

RESUMO

This paper aims to characterize halophilic bacteria inhabiting Algerian Saline Ecosystems (Sebkha and Chott) located in arid and semi-arid ecoclimate zones (Northeastern Algeria). In addition, screening of enzymatic activities, heavy metal tolerance and antagonistic potential against phytopathogenic fungi were tested. A total of 74 bacterial isolates were screened and phylogenetically characterized using 16S rRNA gene sequencing. The results showed a heterogeneous group of microorganisms falling within two major phyla, 52 strains belonging to Firmicutes (70.2%) and 22 strains (30.8%) of γ-Proteobacteria. In terms of main genera present, the isolates were belonging to Bacillus, Halobacillus, Lentibacillus, Oceanobacillus, Paraliobacillus, Planomicrobium, Salicola, Terribacillus, Thalassobacillus, Salibacterium, Salinicoccus, Virgibacillus, Halomonas, Halovibrio, and Idiomarina. Most of the enzymes producers were related to Bacillus, Halobacillus, and Virgibacillus genera and mainly active at 10% of growing salt concentrations. Furthermore, amylase, esterase, gelatinase, and nuclease activities ranked in the first place within the common hydrolytic enzymes. Overall, the isolates showed high minimal inhibitory concentration values (MIC) for Ni2+ and Cu2+ (0.625 to 5 mM) compared to Cd2+ (0.1 to 2 mM) and Zn2+ (0.156 to 2 mM). Moreover, ten isolated strains belonging to Bacillus, Virgibacillus and Halomonas genera, displayed high activity against the pathogenic fungi (Botrytis cinerea, Fusarium oxyporum, F. verticillioides and Phytophthora capsici). This study on halophilic bacteria of unexplored saline niches provides potential sources of biocatalysts and novel bioactive metabolites as well as promising candidates of biocontrol agents and eco-friendly tools for heavy metal bioremediation.


Assuntos
Antibiose , Bactérias/isolamento & purificação , Bactérias/metabolismo , Biota , Microbiologia Ambiental , Salinidade , Argélia , Bactérias/classificação , Bactérias/genética , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Fungos/crescimento & desenvolvimento , Hidrolases/análise , Metais Pesados/metabolismo , Metais Pesados/toxicidade , Testes de Sensibilidade Microbiana , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
7.
Mikrobiyol Bul ; 53(3): 262-273, 2019 Jul.
Artigo em Turco | MEDLINE | ID: mdl-31414628

RESUMO

Helicobacters have wide host diversity due to the their particular virulence and environmental factors and may cause infections in humans. As they live in and around the stomach the group is called as gastric helicobacters which particularly consists of Helicobacter pylori and Helicobacter heilmanni, Helicobacter felis, Helicobacter salomonis and many other species, as well. In this study, it was aimed to evaluate 195 patients (119 urban and 76 rural residents, 121 female and 74 male individuals between 18 and 93 years of age) in terms of gastric Helicobacter (H.pylori, H.felis and H.heilmanii) who have admitted to the Health Research and Application Center of Kafkas University Endoscopy Unit of the General Surgery Department with the complaints of abdominal pain. For this purpose, biopsy specimens obtained from various parts of the stomach (corpus and antrum) by endoscopy were analyzed with histopathological examination and PCR. Histopathological analysis sections were stained with May-Grunwald-Giemsa and spiral-shaped helicobacters attached to the surface of the epithelium were investigated. For the direct analysis of Helicobacter in biopsy samples, 16S rRNA gene based genus-specific and urease B gene based species-specific PCR methods were used. Out of the 195 cases that were histopathologically evaluated 163 (83.58%) were found to be positive for gastric Helicobacter, while five were suspected and 27 were negative. Helicobacter spp. DNA were detected in 107 (54.87%) samples, of these samples 91 were histopathologically positive, 13 were negative and three were suspicious samples. Eighty seven (44.61%) of the samples were identified as H.pylori by species-specific PCR. H.felis and H.heilmannii could not be detected in any of the samples; meanwhile genus-specific PCR positive 20 samples were not identified. In this study, 42.85% of the individuals living in urban area and 47.36% of those living in rural area were identified as H.pylori positive. 46.28% of women and 41.89% of men were positive for H.pylori. The age range of H.pylori positive individuals were as follows: 60% of the individuals were between 15-24 years, 60.27% of the individuals were between 25-44 years, 34.66% of the individuals were between 45-64 years and 29.72% of the individuals were 65 and over. 42.64% of the cat or dog owners were found as H.pylori positive whereas H.pylori was positive in 45.66% of the individuals who do not own animals. No significant relationship was found between these determinants and the prevalence of the disease (p> 0.05). However, the positivity of H.pylori was higher in the 25-44 active working age group due to the increased agent exposure (p<0.05). This study is the first study on the prevalence of H.pylori in humans and analysis of possible risk factors in the region and hoped to provide useful information for the researchers working in this field.


Assuntos
Dor Abdominal/etiologia , Dor Abdominal/microbiologia , Infecções por Helicobacter , Animais , Biópsia , Gatos , Cães , Feminino , Infecções por Helicobacter/complicações , Infecções por Helicobacter/diagnóstico , Helicobacter pylori , Humanos , Masculino , RNA Ribossômico 16S/genética , Medição de Risco
8.
Mikrobiyol Bul ; 53(3): 274-284, 2019 Jul.
Artigo em Turco | MEDLINE | ID: mdl-31414629

RESUMO

Coxiella burnetii is the causative agent of Q fever, a zoonotic infection. The bacteria is a gram-negative, pleomorphic, coccobacilli and capable to survive and proliferate within the host cell's phagolysosome. There are two morphological cell types of C.burnetii including small and large cell variants. C.burnetii is divided into phase I and phase II serologically variants according to LPS structure in the cell wall. Phase I is the natural phase found in infected animals or humans and is highly infectious. Phase II is not very infectious and could be obtained only in laboratories after serial passages in cell cultures or embryonated egg cultures. Q fever can be asymptomatic (in 50% of the cases), acute or chronic. Major presentations of acute Q fever are flu-like illness, pneumonia, and hepatitis, whereas the chronic form presents mainly as infective endocarditis. The aim of this study was to obtain C.burnetii phase II variant from C.burnetii phase I variant by a phase change study. In this study, C.burnetii was isolated by cell culture method from the heart valve tissue of a Q fever endocarditis case. C.burnetii phase I antigen for the indirect fluorescent antibody test (IFAT) was prepared from the isolated strain. For the isolation and identification of C.burnetii, heart valve tissue of the patient was homogenized and DNA was extracted by tissue extraction kit. C.burnetii DNA in the valve tissue was determined by real-time PCR (Rt-PCR). This C.burnetii DNA positive specimen was inoculated into Vero cells by shell vial centrifugation method. The scraped Vero cells were fixed on the slides after one week of incubation and IFAT was performed using C.burnetii phase I IgG positive sera, bacteria that were grown in and surrounding the Vero cells stained apple green were determined microscopically. Infected cells were disrupted by freeze and thaw method to obtain bacterial suspension. The DNA obtained from the bacterial suspension was again found to be positive for C.burnetii by Rt-PCR. Isolation sample was found to be positive in PCR at an earlier cycle compared to heart tissue sample, thus the bacterial growth was also confirmed with PCR. 16S ribosomal RNA gene of our isolate was amplified by PCR using 27F and 1492 primers and then sequenced. The DNA sequences were compared with reference DNA sequences of GeneBank; and the nucleotide sequence of the 16S ribosomal RNA gene of our isolate was found to be 99% similar to C.burnetii strain ATCC VR-615 an accession number NR104916. Serial cell culture passages of the isolated strain were performed to obtain C.burnetii phase II variant from C.burnetii phase I variant. After each passage, presence of phase change was investigated by IFAT using C.burnetii phase I and phase II IgG positive sera. At the end of 17 cell culture passages, phase change could not be observed. C.burnetii phase I IFAT antigen was prepared from the obtained bacterial suspension. In this study, we presented the isolation and identification of C.burnetii by cell culture, molecular and serological methods from the heart valve of a patient with endocarditis for the first time in our country.


Assuntos
Coxiella burnetii , Endocardite , Valvas Cardíacas , Febre Q , Animais , Antígenos de Bactérias/isolamento & purificação , Antígenos de Bactérias/metabolismo , Cercopithecus aethiops , Coxiella burnetii/genética , Coxiella burnetii/isolamento & purificação , Endocardite/microbiologia , Valvas Cardíacas/microbiologia , Humanos , Febre Q/microbiologia , RNA Ribossômico 16S/genética , Turquia , Células Vero
9.
Mikrobiyol Bul ; 53(3): 343-347, 2019 Jul.
Artigo em Turco | MEDLINE | ID: mdl-31414636

RESUMO

Globicatella sanguinis is catalase-negative, alpha-hemolytic, nonmotile, facultative anaerobic grampositive cocci, identified as a new species in 1992. Since the colony morphology in blood agar and microscopic appearance resembles streptococci, it is thought that some of the isolates previously identified in the Streptococcus viridans group were G.sanguinis species. G.sanguinis has been isolated from various clinical specimens, its species identification and antibiotic susceptibility have been tested since the year it was identified. Clinical specimens in which it is isolated include various mucosal surfaces, blood, urine, wound and cerebrospinal fluid. In this report, considering also the literature information, a case of G.sanguinis which is thought to cause meningitis was presented. Our case is a 39-year-old female patient with a lumboperitoneal shunt. The patient was admitted to the neurosurgery clinic with a headache and vision loss and was hospitalized in the service with a pre-diagnosis of pseudotumor cerebri. Neurological examination revealed no pathological findings. Eye examination revealed mild papillary edema, local retinal hemorrhage, and bilateral expansion in retinal vascularization. There was no pathologic findings in the brain magnetic resonance imaging. The colonies resembling alpha hemolytic streptococci were isolated from the cerebrospinal fluid taken upon the development of neck stiffness, fever, and tachycardia on the 10th day of hospitalization of the lumbo-peritoneal shunt administered patient. The identification of the isolate was determined in Bruker IVD MALDI Biotyper 2.3 (Bruker Daltonik GmbH, Bremen, Germany), available in our laboratory and it was identified as G.sanguinis (KJ680157.1) with a score of > 2. The definite identification of the isolate at the species level was made by 16S rDNA sequence analysis and it was determined that the bacterium was G.sanguinis with 100% similarity and coverage. The minimum inhibitory concentration (MIC) for some of the antibiotics was determined by the agar gradient method. The MIC values were found as; linezolid 0.50 µg/ml, vancomycin 0.75 µg/ ml, imipenem 0.75 µg/ml, meropenem 3 µg/ml, penicillin G 6 µg/ml and cefotaxime > 32 µg/ml. It is known that these rare isolates can be isolated in greater numbers along with the introduction of MALDITOF MS-based devices in many laboratories. Following greater numbers of isolation of this rare species of bacteria, our knowledge about its clinical significance, placement in the flora and antibiotic susceptibility will also be expanded.


Assuntos
Aerococcaceae , Meningite , Derivação Peritoneovenosa , Adulto , Aerococcaceae/efeitos dos fármacos , Aerococcaceae/genética , Antibacterianos/farmacologia , Feminino , Alemanha , Humanos , Meningite/complicações , Meningite/microbiologia , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S/genética
10.
Vet Parasitol ; 273: 71-79, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31446256

RESUMO

Tick-borne diseases (TBD) constitute an important group of illness affecting animals and humans worldwide. In Brazil, carthorses are frequently exposed to ticks and tick-borne pathogens, leading to impairment of horse performance and imposing restrictions by the international veterinary authorities for the importation of horses. Accordingly, this study has aimed to i) determine the prevalence of the TBD agents Theileria equi, Babesia caballi, Ehrlichia spp., and hemotropic mycoplasmas in carthorses, ii) identify the tick species parasitizing the animals, and iii) determine factors associated with exposure/infection in Foz do Iguaçu City, Parana state, southern Brazil. A total of 103 carthorses were screened for anti-T. equi and anti-Ehrlichia spp. antibodies by indirect fluorescent antibody assays (IFA). Samples were also tested by PCR assays targeting the 18S rRNA gene of T. equi and B. caballi, and 16S rRNA gene of hemoplasmas. Additionally, PCR assays targeting the 16S rRNA, disulfide bond formation protein (dsb) and tandem repeat proteins 36 (trp36) genes of Ehrlichia spp. were also performed. Antibodies to T. equi and Ehrlichia spp. were detected in 43/103 (41.75%; 95% CI: 32.10-51.88%) and 5/103 (4.85%; 95% CI: 1.59-10.97%) horses by IFA, respectively. DNA of T. equi and B. caballi were found in 25/103 (24.27%; 95% CI: 16.36-33.71%) and 10/103 (9.71%; 95% CI: 4.75-17.13%) carthorses, respectively, and all tested negative for Ehrlichia spp. and hemoplasmas. All sequences showed ≥99% identity with multiple T. equi and B. caballi 18S rRNA gene sequences deposited in GenBank. Overall, 191 Dermacentor nitens ticks were collected from 25/103 (24.27%) animals. Carthorses older than 5 years were more likely to be positive for T. equi (p < 0.05). In conclusion, equine piroplasmosis agents are highly prevalent in carthorses from Foz do Iguaçu City. The low prevalence of Ehrlichia spp. found may be due to the absence of Amblyomma ticks infesting animals, which should be further investigated.


Assuntos
Doenças dos Cavalos/microbiologia , Doenças dos Cavalos/parasitologia , Infestações por Carrapato/veterinária , Doenças Transmitidas por Carrapatos , Carrapatos/microbiologia , Carrapatos/parasitologia , Animais , Brasil , Técnica Indireta de Fluorescência para Anticorpo , Cavalos , RNA Ribossômico 16S/genética , RNA Ribossômico 18S/genética , Theileria/genética , Infestações por Carrapato/microbiologia , Infestações por Carrapato/parasitologia , Doenças Transmitidas por Carrapatos/microbiologia , Doenças Transmitidas por Carrapatos/parasitologia
11.
An Acad Bras Cienc ; 91(2): e20180394, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31269105

RESUMO

The petrochemical industry has played a considerable role in generation and release of waste in the environment. Activated sludge and facultative lagoons are commonly used for domestic and industrial wastewater treatment due to their low-cost and minimal need for operational requirements. Microorganisms present in wastewater treatment plant (WWTP) are responsible for most nutrient removal. In this study, microbiological and physicochemical parameters were used to estimate changes in bacterial community in a petrochemical industrial WWTP. The activated sludge was the place with higher heterotrophic bacterial quantification. Denitrifying bacteria was reduced at least 5.3 times throughout all collections samples. We observe a decrease in the total Kjeldahl nitrogen, oxygen demand and phosphate throughout the WWTP. In this work, we also use Matrix-Assisted Laser Desorption Ionisation-Time-of-Flight Mass Spectrometry (MALDI-TOF MS) for bacteria isolates identification comparing with 16S rDNA sequencing. The MALDI-TOF MS allowed the identification of 93% of the isolates and only 5% show different results from 16S rDNA sequencing showing that the MALDI-TOF MS can be a tool for identifying environmental bacteria. The observation of microbial community dynamics in the WWTP is important in order to understand the functioning of the ecological structure formed in a specific environment.


Assuntos
Bactérias/metabolismo , Águas Residuárias/química , Águas Residuárias/microbiologia , Purificação da Água/métodos , Bactérias/classificação , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Espectrometria de Massas , Indústria de Petróleo e Gás , RNA Ribossômico 16S/genética , Eliminação de Resíduos Líquidos/métodos
12.
World J Microbiol Biotechnol ; 35(8): 117, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31332532

RESUMO

Iron- and sulfur-oxidizing bacteria inhabiting rice rhizoplane play a significant role on arsenic biogeochemistry in flooded rice paddies, influencing arsenic translocation to rice grains. In the present study, the selective pressure of arsenic species on these microbial populations was evaluated. Rice roots from continuously flooded plants were incubated in iron sulfide (FeS) gradient tubes and exposed to either arsenate or arsenite. The biomass developed in the visible iron-oxidation band of the enrichments was analyzed by Scanning Electron Microscopy and Energy-Dispersive Spectroscopy (SEM-EDS) and the bacterial communities were characterized by 16S rRNA gene sequencing. Different Proteobacteria communities were selected depending on exposure to arsenate and arsenite. Arsenate addition favored the versatile iron-oxidizers Dechloromonas and Azospira, associated to putative iron (hydr)oxide crystals. Arsenite exposure decreased the diversity in the enrichments, with the development of the sulfur-oxidizer Thiobacillus thioparus, likely growing on sulfide released by FeS. Whereas sulfur-oxidizers were observed in all treatments, iron-oxidizers disappeared when exposed to arsenite. These results reveal a strong impact of different inorganic arsenics on rhizospheric iron-oxidizers as well as a crucial role of sulfur-oxidizing bacteria in establishing rice rhizosphere communities under arsenic pressure.


Assuntos
Arsênico/metabolismo , DNA Bacteriano/isolamento & purificação , Oryza/efeitos dos fármacos , Oryza/microbiologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/microbiologia , Arseniatos/metabolismo , Arsenitos/metabolismo , DNA Bacteriano/genética , Ferro/metabolismo , Oxirredução , Proteobactérias/efeitos dos fármacos , Proteobactérias/isolamento & purificação , Proteobactérias/metabolismo , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/isolamento & purificação , Solo/química , Microbiologia do Solo , Poluentes do Solo/metabolismo , Enxofre/metabolismo
13.
Bioresour Technol ; 289: 121736, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31288961

RESUMO

This study investigated a new method of multiple-cycle operation of a sulphur-cycle-enhanced biological phosphorus (P) removal system to maintain good phosphorus removal performance at a high temperature (30 °C). The findings demonstrate that P removal was low and unstable under a normal cycle (77 ±â€¯18%), but multiple cycles resulted in a high and quite stable level of P removal (88 ±â€¯9%). Moreover, in the normal mode, the polyhydroxyalkanoate levels increased significantly from 2 to 15 mg C/g of VSS, the glycogen level doubled from 5 to 10 mg C/g of VSS and the polyhydroxyalkanoate and glycogen levels were maintained at considerably low levels after multiple cycles (only 5 C/g of VSS). The 16S rRNA high-throughput sequencing analysis revealed that the genera Thioalbus and Psychrobacter in the gamma-Proteobacteria class were the key functional communities. These findings suggest a high level of P removal with multiple cycles of sulphur-cycle enhanced biological phosphorus removal.


Assuntos
Fósforo/metabolismo , Enxofre/metabolismo , Reatores Biológicos , Glicogênio/metabolismo , Temperatura Alta , RNA Ribossômico 16S/genética
14.
Phytochemistry ; 166: 112059, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31280092

RESUMO

The cyanobacterial phylum is currently divided into five subsections (I-V), with the latter two containing no or false-branching (nostocalean) and true-branching (stigonematalean) cyanobacteria. Although morphological traits (such as cellular division and secondary branches) clearly separate both types of heterocytous cyanobacteria, molecular evidence indicates that stigonematalean cyanobacteria (Subsection V) do not form a monophyletic group but instead are interspersed and nested within the nostocalean cyanobacteria (Subsection IV). To further resolve the phylogeny of heterocytous cyanobacteria, we here analyzed the distribution of heterocyte glycolipids (HGs) in the true-branching cyanobacterium Stigonema ocellatum SAG 48.90 (type genus of Subsection V) and compared it with the HG inventory of other stigonematalean and nostocalean cyanobacteria. The most dominant HGs in S. ocellatum SAG 48.90 were 1-(O-hexose)-27-keto-3,25-octacosanediol (HG28 keto-diol) and 1-(O-hexose)-3,25,27-octacosanetriol (HG28 triol), which together constituted ca. 94% of all HGs. In addition, 1-(O-hexose)-3-keto-27-octacosanols (HG28 keto-ols), 1-(O-hexose)-3,27-octacosanediols (HG28 diols), 1-(O-hexose)-3-keto-27,29-triacontanediol (HG30 keto-diol) and 1-(O-hexose)-3,27,29-triacontanetriol (HG30 triol) occurred in minor abundances. Heterocyte glycolipids previously reported to be unique for stigonematalean cyanobacteria, i.e. 1-(O-hexose)-3,29,31-dotriacontanetriols (HG32 triols) and 1-(O-hexose)-3-keto-29,31-dotriacontanediols (HG32 keto-diols), were not detected in S. ocellatum SAG 48.90. Comparison of the HG distribution pattern with those of other heterocytous cyanobacteria indicated that S. ocellatum SAG 48.90 is most closely related to the nostocalean families Rivulariaceae and Scytonemataceae, which is complementary to reconstructed 16S rRNA gene sequence phylogenies. Our HG-based data thus provides evidence for the polyphyly of stigonematalean cyanobacteria, independent from molecular approaches, and points to the need for a critical re-evaluation of the current taxonomy of heterocytous cyanobacteria.


Assuntos
Cianobactérias/classificação , Cianobactérias/metabolismo , Glicolipídeos/metabolismo , Filogenia , Cianobactérias/genética , RNA Ribossômico 16S/genética
15.
Int J Syst Evol Microbiol ; 69(9): 2717-2722, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31361214

RESUMO

A Gram-reaction-negative, aerobic, flagellated and coccoid-shaped bacterial strain, designated SM1702T, was isolated from Antarctic intertidal sediment collected off Ardely Island, West Antarctica. The strain grew at 0-30 °C and with 0.5-5.0 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences and single-copy orthologous clusters both showed that strain SM1702T, together with Poseidonibacter lekithochrous, occupied an independent phylogenetic branch, sharing the highest 16S rRNA gene sequence similarity with type strain of the latter (95.6 %). The major fatty acids were summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c), C16 : 0, and summed feature 2 (C14 : 0 3-OH and/or iso-C16 : 1 I). Polar lipids were phosphatidylethanolamine and phosphatidylglycerol. The genomic DNA G+C content of strain SM1702T was 27.1 mol%. Based on the results of the polyphasic characterisation for strain SM1702T, it is identified as the representative of a novel species of Poseidonibacter, for which the name Poseidonibacter antarcticus sp. nov. is proposed. The type strain of Poseidonibacter antarcticus is SM1702T (=MCCC 1K03471T=KCTC 62796T).


Assuntos
Campylobacteraceae/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar/microbiologia , Regiões Antárticas , Técnicas de Tipagem Bacteriana , Composição de Bases , Campylobacteraceae/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
16.
Int J Syst Evol Microbiol ; 69(9): 2870-2876, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31259683

RESUMO

Paenibacillus durusand Paenibacillus azotofixans, both Gram-stain-positive and endospore-forming bacilli, have been considered to be a single species. However, a preliminary computation of their average nucleotide identity (ANI) values suggested that these species are not synonyms. Given this, the taxonomic attributions of these species were evaluated through genomic and phylogenomic approaches. Although the identity of 16S rRNA gene sequences of P. durus DSM 1735T and P. azotofixans ATCC 35681T are above the circumscription species threshold, genomic metrics analyses indicate otherwise. ANI, gANI and OrthoANI values computed from their genome sequences were around 92 %, below the species limits. Digital DNA-DNA hybridization and MUMi estimations also corroborated these observations. In fact, in all metrics, Paenibacillus zanthoxyli JH29T seemed to be more similar to Paenibacillus azotofixans. ATCC 35681T than P. durus DSM 1735T. Phylogenetic analyses based on concatenated core-proteome and concatenated gyrB, recA, recN and rpoB genes confirmed that P. zanthoxyli is the closest Paenibacillus species to P. azotofixans. A review of the phenotypic profiles from these three species revealed that their biochemical repertoires are very similar, although P. azotofixans ATCC 35681T can be differentiated from P. durus DSM1735T in 13 among more than 90 phenotypic traits. Considering phylogenetic and genomic analyses, Paenibacillus azotofixans should be considered as an independent species, and not as a later synonym of Paenibacillus durus.


Assuntos
Paenibacillus/classificação , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Genes Bacterianos , Genômica , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , Fenótipo , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
17.
Int J Syst Evol Microbiol ; 69(9): 2739-2749, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31259682

RESUMO

Three bacterial strains, 30S-ANTBAC, 103A-SOEBACH and 59G- WUEMPEL, were isolated from two small freshwater creeks and an intermittent pond near Salzburg, Austria. Phylogenetic reconstructions with 16S rRNA gene sequences and, genome based, with amino acid sequences obtained from 119 single copy genes showed that the three strains represent a new genus of the family Cytophagaceae within a clade formed by the genera Pseudarcicella, Arcicella and Flectobacillus. blast searches suggested that the new genus comprises widespread freshwater bacteria. Phenotypic, chemotaxonomic and genomic traits were investigated. Cells were rod shaped and were able to glide on soft agar. All strains grew chemoorganotrophically and aerobically, were able to assimilate pectin and showed an intense red pigmentation putatively due to various carotenoids. Two strains possessed genes putatively encoding proteorhodopsin and retinal biosynthesis. Genome sequencing revealed genome sizes between 2.5 and 3.1 Mbp and G+C contents between 38.0 and 42.7 mol%. For the new genus we propose the name Aquirufa gen. nov. Pairwise-determined whole-genome average nucleotide identity values suggested that the three strains represent two new species within the new genus for which we propose the names Aquirufa antheringensis sp. nov. for strain 30S-ANTBACT (=JCM 32977T =LMG 31079T=DSM 108553T) as type species of the genus, to which also belongs strain 103A-SOEBACH (=DSM 108555=LMG 31082) and Aquirufa nivalisilvae sp. nov. for strain 59G-WUEMPELT (=LMG 31081T =DSM 108554T).


Assuntos
Cytophagaceae/classificação , Água Doce/microbiologia , Filogenia , Áustria , Técnicas de Tipagem Bacteriana , Composição de Bases , Cytophagaceae/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/química
18.
Int J Syst Evol Microbiol ; 69(9): 2862-2869, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31274399

RESUMO

Four Gram-stain positive, rod-shaped bacterial isolates, strains JZ R-183T, JZ RK-117, DI-46 and JZ R-35T, were recovered from bulk tank raw cow's milk from three different dairy farms in Germany. Analysis of their 16S rRNA gene sequences indicated that these isolates belonged to the family Micrococcaceae, closely related to the genera Arthrobacter, Neomicrococcus,Glutamicibacter and Citricoccus. The 16S rRNA gene sequence similarity between the isolates and the next related type strains was below 97.3 %. Phylogenetic analysis of 16S rRNA, recA and gyrB genes revealed that these isolates formed two different groups in an independent cluster within the family Micrococcaceae. Chemotaxonomic analyses determined anteiso-C15 : 0 as predominant fatty acid, but also large amounts of iso-C15 : 0, iso-C16 : 0 and iso-C17 : 0 were detected. The menaquinones MK-9(H2) and MK-7(H2) were present in all of the isolates and the polar lipid pattern contained the phospholipids diphosphatidylglycerol, phosphatidylglycerol and phosphatidylinositol and a glycolipid. The peptidoglycan type of the isolates was A4α, with alanine, lysine and glutamate as dominating cell wall amino acids. The fatty acid and menaquinone profile differentiated the strains from the genera Arthrobacter, Neomicrococcus,Citricoccus and Glutamicibacter. The results of phylogenetic, phenotypic and chemotaxonomic analyses indicated that the isolates belonged to two novel species of a novel genus, for which the names Galactobacter caseinivorans gen. nov., sp. nov. and Galactobacter valiniphilus sp. nov. are proposed. The type strains are JZ R-183T (=DSM 107700T=LMG 30902T) and JZ R-35T (=DSM 107699T=LMG 30901T).


Assuntos
Micrococcaceae/classificação , Leite/microbiologia , Filogenia , Animais , Carga Bacteriana , Técnicas de Tipagem Bacteriana , Composição de Bases , Bovinos/microbiologia , Parede Celular/química , DNA Bacteriano/genética , Ácidos Graxos/química , Feminino , Alemanha , Glicolipídeos/química , Micrococcaceae/isolamento & purificação , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
19.
Int J Syst Evol Microbiol ; 69(9): 2907-2913, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31274405

RESUMO

The genus Acidithiobacillus currently includes seven species with validly published names, which fall into two major groups, those that can oxidize ferrous iron and those that do not. All seven species can use zero-valent sulfur and reduced sulfur oxy-anions as electron donors, are obligately chemolithotrophic and acidophilic bacteria with pH growth optima below 3.0. The 16S rRNA gene of a novel strain (CJ-2T) isolated from circum-neutral pH mine drainage showed 95-97 % relatedness to members of the genus Acidithiobacillus. Digital DNA-DNA hybridization (dDDH) values between strains and whole-genome pairwise comparisons between the CJ-2T strain and the reference genomes available for members of the genus Acidithiobacillus confirmed that CJ-2Trepresents a novel species of this genus. CJ-2T is a strict aerobe, oxidizes zero-valent sulfur and reduced inorganic sulfur compounds but does not use ferrous iron or hydrogen as electron donors. The isolate is mesophilic (optimum growth temperature 25-28 °C) and extremely acidophilic (optimum growth pH 3.0), though its pH optimum and maximum were significantly higher than those of non-iron-oxidising acidithiobacilli with validly published names. The major fatty acids of CJ-2T were C18 : 1ω7c, C:16 : 1ω7c/iso-C15 : 0 2-OH, C16 : 0 and C19 : 0 cyclo ω8c and the major respiratory quinone present was Q8. The name Acidithiobacillussulfuriphilus sp. nov. is proposed, the type strain is CJ-2T (=DSM 105150T=KCTC 4683T).


Assuntos
Acidithiobacillus/classificação , Mineração , Filogenia , Enxofre/metabolismo , Microbiologia da Água , Acidithiobacillus/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Concentração de Íons de Hidrogênio , Ferro , Hibridização de Ácido Nucleico , Oxirredução , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , País de Gales
20.
Int J Syst Evol Microbiol ; 69(9): 2854-2861, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31274408

RESUMO

A Gram-stain-negative, non-motile, mesophilic, short rod-shaped, aerobic bacterium designated as 318-1T was isolated from a marine sediment collected from Masan Bay, South Korea. Strain 318-1T grew optimally at pH 6-7, at 30 °C and in the presence of 2-3 % (w/v) NaCl, tolerant of up to 8 % (w/v) NaCl, and accumulated poly-ß-hydroxybutyrate (PHB). A comparative analysis of 16S rRNA gene sequences revealed that strain 318-1T formed a distinct phyletic lineage in the genus Ruegeria (family Rhodobacteraceae, class Alphaproteobacteria) and showed high sequence similarity to Ruegeria halocynthiae DSM 27839T (96.5 %) and Shimia haliotis DSM 28453T (96.3 %). Comparing the genome sequence of 318-1T with those of the type strains of seven species of the genus Rugeria and two species of the genus Shimia, the values obtained were below the thresholds with analysis of average nucleotide identities (ANI, 71.6-76.8 %) and in silico DNA-DNA hybridisation, Genome-to-Genome Distance Calculator (GGDC, 18.5-20.6 %). The DNA G+C content was 65.75 mol%. Chemotaxonomic data [predominant quinone ubiquinone Q10; polar lipid profile consisting of major compounds phosphatidylcholine (PC), phosphatidylglycerol (PG), an unidentified aminolipid and an unidentified lipid; major fatty acids summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c)] supported the affiliation of strain 318-1T to the genus Ruegeria. Genomic, chemotaxonomic, and phenotypic differentiation of strain 318-1T from the members of the genus Ruegeria support it as a novel species. On the basis of the results in this study, a novel species, Ruegeria lutea sp. nov., is proposed. The type strain is 318-1T (=JCM 30927T=KEMB 7306-525T=KCTC 72105T).


Assuntos
Sedimentos Geológicos/microbiologia , Filogenia , Rhodobacteraceae/classificação , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , Baías , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Rhodobacteraceae/isolamento & purificação , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
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