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1.
Invest Ophthalmol Vis Sci ; 63(2): 21, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35142786

RESUMO

Purpose: To determine the possible microbiome related to Vogt-Koyanagi-Harada (VKH) disease in comparison to patients with noninfectious anterior scleritis and healthy people. Methods: Fecal samples were extracted from 42 individuals, including 11 patients with active VKH, 11 healthy people, and 20 patients with noninfectious anterior scleritis. We amplified the V3 to V4 16S ribosomal DNA (rDNA) region to obtain the target sequence. Then, the target sequence was amplified by polymerase chain reaction. The obtained target sequences were sequenced by high-throughput 16S rDNA analysis. Results: At the genus level, there were three enriched (Stomatobaculum, Pseudomonas, Lachnoanaerobaculum) and two depleted (Gordonibacter, Slackia) microbes that were detected only in patients with VKH. There were 10 enriched and 12 depleted microbes that were observed in both patients with VKH disease and noninfectious anterior scleritis (P < 0.05). The interactions of these microbes were graphed. Tyzzerella and Eggerthella were the nodes of interaction between these microorganisms, which were regulated by both positive and negative aspects, but the expression level in patients with active VKH was upregulated. Conclusions: Special or nonspecial enrichment and decreased intestinal microbes were observed in patients with active VKH. The action mechanism of these microbes needs further study.


Assuntos
Actinobacteria/fisiologia , Clostridiales/fisiologia , Microbioma Gastrointestinal/fisiologia , Pseudomonas/fisiologia , Síndrome Uveomeningoencefálica/microbiologia , Adulto , Estudos de Casos e Controles , DNA Bacteriano/genética , Disbiose/microbiologia , Fezes/microbiologia , Feminino , Técnicas de Genotipagem , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , RNA Ribossômico 16S/genética , Esclerite/microbiologia
2.
Int J Mol Sci ; 23(3)2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35163015

RESUMO

Nowadays, the worldwide agriculture is experiencing a transition process toward more sustainable production, which requires the reduction of chemical inputs and the preservation of microbiomes' richness and biodiversity. Plants are no longer considered as standalone entities, and the future of agriculture should be grounded on the study of plant-associated microorganisms and all their potentiality. Moreover, due to the climate change scenario and the resulting rising incidence of abiotic stresses, an innovative and environmentally friendly technique in agroecosystem management is required to support plants in facing hostile environments. Plant-associated microorganisms have shown a great attitude as a promising tool to improve agriculture sustainability and to deal with harsh environments. Several studies were carried out in recent years looking for some beneficial plant-associated microbes and, on the basis of them, it is evident that Actinomycetes and arbuscular mycorrhizal fungi (AMF) have shown a considerable number of positive effects on plants' fitness and health. Given the potential of these microorganisms and the effects of climate change, this review will be focused on their ability to support the plant during the interaction with abiotic stresses and on multi-omics techniques which can support researchers in unearthing the hidden world of plant-microbiome interactions. These associated microorganisms can increase plants' endurance of abiotic stresses through several mechanisms, such as growth-promoting traits or priming-mediated stress tolerance. Using a multi-omics approach, it will be possible to deepen these mechanisms and the dynamic of belowground microbiomes, gaining fundamental information to exploit them as staunch allies and innovative weapons against crop abiotic enemies threatening crops in the ongoing global climate change context.


Assuntos
Actinobacteria/fisiologia , Biologia Computacional/métodos , Produtos Agrícolas/crescimento & desenvolvimento , Micorrizas/fisiologia , Mudança Climática , Produtos Agrícolas/microbiologia , Genômica , Metabolômica , Desenvolvimento Vegetal , Microbiologia do Solo , Estresse Fisiológico , Biologia de Sistemas
3.
Mol Microbiol ; 117(1): 179-192, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34687261

RESUMO

WhiB7/WblC is a transcriptional factor of actinomycetes conferring intrinsic resistance to multiple translation-inhibitory antibiotics. It positively autoregulates its own transcription in response to the same antibiotics. The presence of a uORF and a potential Rho-independent transcription terminator in the 5' leader region has suggested a possibility that the whiB7/wblC gene is regulated via a uORF-mediated transcription attenuation. However, experimental evidence for the molecular mechanism to explain how antibiotic stress suppresses the attenuator, if any, and induces transcription of the whiB7/wblC gene has been lacking. Here we report that the 5' leader sequences of the whiB7/wblC genes in sub-clades of actinomycetes include conserved antiterminator RNA structures. We confirmed that the putative antiterminator in the whiB7/wblC leader sequences of both Streptomyces and Mycobacterium indeed suppresses Rho-independent transcription terminator and facilitates transcription readthrough, which is required for WhiB7/WblC-mediated antibiotic resistance. The antibiotic-mediated suppression of the attenuator can be recapitulated by amino acid starvation, indicating that translational inhibition of uORF by multiple signals is a key to induce whiB7/wblC expression. Our findings of a mechanism leading to intrinsic antibiotic resistance could provide an alternative to treat drug-resistant mycobacteria.


Assuntos
Regiões 5' não Traduzidas/genética , Actinobacteria/genética , Antibacterianos/farmacocinética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Mycobacterium/genética , Streptomyces coelicolor/genética , Actinobacteria/fisiologia , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , Mycobacterium/fisiologia , Ribossomos/metabolismo , Streptomyces coelicolor/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcrição Genética
4.
BMC Microbiol ; 21(1): 335, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34876006

RESUMO

BACKGROUND: The native potatoes (Solanum tuberosum subsp. tuberosum L.) grown in Chile (Chiloé) represent a new, unexplored source of endophytes to find potential biological control agents for the prevention of bacterial diseases, like blackleg and soft rot, in potato crops. RESULT: The objective of this study was the selection of endophytic actinobacteria from native potatoes for antagonistic activity against Pectobacterium carotovorum subsp. carotovorum and Pectobacterium atrosepticum, and their potential to suppress tissue maceration symptoms in potato tubers. This potential was determined through the quorum quenching activity using a Chromobacterium violaceaum ATCC 12472 Wild type (WT) bioassay and its colonization behavior of the potato plant root system (S. tuberosum) by means of the Double labeling of oligonucleotide probes for fluorescence in situ hybridization (DOPE-FISH) targeting technique. The results showed that although Streptomyces sp. TP199 and Streptomyces sp. A2R31 were able to inhibit the growth of the pathogens, only the Streptomyces sp. TP199 isolate inhibited Pectobacterium sp. growth and diminished tissue maceration in tubers (p ≤ 0.05). Streptomyces sp. TP199 had metal-dependent acyl homoserine lactones (AHL) quorum quenching activity in vitro and was able to colonize the root endosphere 10 days after inoculation. CONCLUSIONS: We concluded that native potatoes from southern Chile possess endophyte actinobacteria that are potential agents for the disease management of soft rot and blackleg.


Assuntos
Actinobacteria/fisiologia , Antibiose/fisiologia , Endófitos/fisiologia , Solanum tuberosum/microbiologia , Actinobacteria/classificação , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Agentes de Controle Biológico/isolamento & purificação , Chile , Endófitos/classificação , Endófitos/genética , Endófitos/isolamento & purificação , Pectobacterium/fisiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Tubérculos/microbiologia , Percepção de Quorum , Streptomyces/classificação , Streptomyces/genética , Streptomyces/isolamento & purificação , Streptomyces/fisiologia
5.
PLoS One ; 16(11): e0260451, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34813629

RESUMO

The mortality rates of COVID-19 vary widely across countries, but the underlying mechanisms remain unelucidated. We aimed at the elucidation of relationship between gut microbiota and the mortality rates of COVID-19 across countries. Raw sequencing data of 16S rRNA V3-V5 regions of gut microbiota in 953 healthy subjects in ten countries were obtained from the public database. We made a generalized linear model (GLM) to predict the COVID-19 mortality rates using gut microbiota. GLM revealed that low genus Collinsella predicted high COVID-19 mortality rates with a markedly low p-value. Unsupervised clustering of gut microbiota in 953 subjects yielded five enterotypes. The mortality rates were increased from enterotypes 1 to 5, whereas the abundances of Collinsella were decreased from enterotypes 1 to 5 except for enterotype 2. Collinsella produces ursodeoxycholate. Ursodeoxycholate was previously reported to inhibit binding of SARS-CoV-2 to angiotensin-converting enzyme 2; suppress pro-inflammatory cytokines like TNF-α, IL-1ß, IL-2, IL-4, and IL-6; have antioxidant and anti-apoptotic effects; and increase alveolar fluid clearance in acute respiratory distress syndrome. Ursodeoxycholate produced by Collinsella may prevent COVID-19 infection and ameliorate acute respiratory distress syndrome in COVID-19 by suppressing cytokine storm syndrome.


Assuntos
Actinobacteria/fisiologia , COVID-19/prevenção & controle , Microbioma Gastrointestinal , Intestinos/microbiologia , SARS-CoV-2/fisiologia , Ácido Ursodesoxicólico/metabolismo , COVID-19/etiologia , COVID-19/patologia , Humanos
6.
PLoS One ; 16(11): e0259465, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34731210

RESUMO

Curtobacterium sp. GD1 was isolated from leaves of conventionally grown soybean in Brazil. It was noteworthy that among all bacteria previously isolated from the same origin, only Curtobacterium sp. GD1 showed a strong chitinase activity. The enzyme was secreted and its production was induced by the presence of colloidal chitin in the medium. The chitinase was partially purified and characterized: molecular weight was approximately 37 kDa and specific activity 90.8 U/mg. Furthermore, Curtobacterium sp. GD1 genome was sequenced and analyzed. Our isolate formed a phylogenetic cluster with four other Curtobacterium spp. strains, with ANIb/ANIm ≥ 98%, representing a new, still non described Curtobacterium species. The circular genome visualization and comparison of genome sequences of strains forming new cluster indicated that most regions within their genomes were highly conserved. The gene associated with chitinase production was identified and the distribution pattern of glycosyl hydrolases genes was assessed. Also, genes associated with catabolism of structural carbohydrates such as oligosaccharides, mixed polysaccharides, plant and animal polysaccharides, as well as genes or gene clusters associated with resistance to antibiotics, toxic compounds and auxin biosynthesis subsystem products were identified. The abundance of putative glycosyl hydrolases in the genome of Curtobacterium sp. GD1 suggests that it has the tools for the hydrolysis of different polysaccharides. Therefore, Curtobacterium sp. GD1 isolated from soybean might be a bioremediator, biocontrol agent, an elicitor of the plant defense responses or simply degrader.


Assuntos
Actinobacteria/fisiologia , Quitina/química , Quitinases/genética , Soja/microbiologia , Sequenciamento Completo do Genoma/métodos , Actinobacteria/classificação , Actinobacteria/isolamento & purificação , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Quitinases/metabolismo , Genoma Bacteriano , Sequenciamento de Nucleotídeos em Larga Escala , Hidrólise , N-Glicosil Hidrolases/genética , N-Glicosil Hidrolases/metabolismo , Filogenia , Folhas de Planta/química , Folhas de Planta/microbiologia , Soja/metabolismo
8.
Cell Host Microbe ; 29(11): 1649-1662.e7, 2021 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-34637779

RESUMO

Saccharibacteria (TM7) are obligate epibionts living on the surface of their host bacteria and are strongly correlated with dysbiotic microbiomes during periodontitis and other inflammatory diseases, suggesting they are putative pathogens. However, due to the recalcitrance of TM7 cultivation, causal research to investigate their role in inflammatory diseases is lacking. Here, we isolated multiple TM7 species on their host bacteria from periodontitis patients. These TM7 species reduce inflammation and consequential bone loss by modulating host bacterial pathogenicity in a mouse ligature-induced periodontitis model. Two host bacterial functions involved in collagen binding and utilization of eukaryotic sialic acid are required for inducing bone loss and are altered by TM7 association. This TM7-mediated downregulation of host bacterial pathogenicity is shown for multiple TM7/host bacteria pairs, suggesting that, in contrast to their suspected pathogenic role, TM7 could protect mammalian hosts from inflammatory damage induced by their host bacteria.


Assuntos
Actinobacteria/patogenicidade , Perda do Osso Alveolar/microbiologia , Fenômenos Fisiológicos Bacterianos , Gengivite/microbiologia , Periodontite/microbiologia , Simbiose , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Actinobacteria/fisiologia , Actinomyces/genética , Actinomyces/isolamento & purificação , Actinomyces/patogenicidade , Actinomyces/fisiologia , Perda do Osso Alveolar/prevenção & controle , Animais , Bactérias/classificação , Bactérias/isolamento & purificação , Bactérias/patogenicidade , Infecções Bacterianas/microbiologia , Infecções Bacterianas/prevenção & controle , Colágeno/metabolismo , Placa Dentária/microbiologia , Regulação para Baixo , Genes Bacterianos , Gengivite/prevenção & controle , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microbiota , Ácido N-Acetilneuramínico/metabolismo , Periodontite/prevenção & controle , Propionibacteriaceae/genética , Propionibacteriaceae/isolamento & purificação , Propionibacteriaceae/patogenicidade , Propionibacteriaceae/fisiologia , Virulência
9.
J Basic Microbiol ; 61(11): 1002-1015, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34528722

RESUMO

The enzyme dextranase is widely used in the sugar and food industries, as well as in the medical field. Most land-derived dextranases are produced by fungi and have the disadvantages of long production cycles, low tolerance to environmental conditions, and low safety. The use of marine bacteria to produce dextranases may overcome these problems. In this study, a dextranase-producing bacterium was isolated from the Rizhao seacoast of Shandong, China. The bacterium, denoted as PX02, was identified as Cellulosimicrobium sp. and its growing conditions and the production and properties of its dextranase were investigated. The dextranase had a molecular weight of approximately 40 kDa, maximum activity at 40°C and pH 7.5, with a stability range of up to 45°C and pH 7.0-9.0. High-performance liquid chromatography showed that the dextranase hydrolyzed dextranT20 to isomaltotriose, maltopentaose, and isomaltooligosaccharides. Hydrolysis by dextranase produced excellent antioxidant effects, suggesting its potential use in the health food industry. Investigation of the action of the dextranase on Streptococcus mutans biofilm and scanning electron microscopy showed that it to be effective both for removing and inhibiting the formation of biofilms, suggesting its potential application in the dental industry.


Assuntos
Actinobacteria/enzimologia , Proteínas de Bactérias/metabolismo , Dextranase/metabolismo , Actinobacteria/classificação , Actinobacteria/isolamento & purificação , Actinobacteria/fisiologia , Antioxidantes/química , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Proteínas de Bactérias/química , Proteínas de Bactérias/farmacologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , China , Dextranase/química , Dextranase/farmacologia , Concentração de Íons de Hidrogênio , Hidrólise , Metais/metabolismo , Peso Molecular , Água do Mar/microbiologia , Streptococcus mutans/efeitos dos fármacos , Especificidade por Substrato , Temperatura
10.
World J Microbiol Biotechnol ; 37(7): 109, 2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34057641

RESUMO

Phosphate solubilizing microorganisms widely exist in plant rhizosphere soil, but report about the P solubilization and multiple growth-promoting properties of rare actinomycetes are scarce. In this paper, a phosphate solubilizing Tsukamurella tyrosinosolvens P9 strain was isolated from the rhizosphere soil of tea plants. Phosphorus-dissolving abilities of this strain were different under different carbon and nitrogen sources, the soluble phosphorus content was 442.41 mg/L with glucose and potassium nitrate as nutrient sources. The secretion of various organic acids, such as lactic acid, maleic acid, oxalic acid, etc., was the main mechanism for P solubilization and pH value in culture was very significant negative correlation with soluble P content. In addition, this strain had multiple growth-promoting characteristics with 37.26 µg/mL of IAA and 72.01% of siderophore relative content. Under pot experiments, P9 strain improved obviously the growth of peanut seedlings. The bacterial communities of peanut rhizoshpere soil were assessed after inoculated with P9 strain. It showed that there was no significant difference in alpha-diversity indices between the inoculation and control groups, but the P9 treatment group changed the composition of bacterial communities, which increased the relative abundance of beneficial and functional microbes, which relative abundances of Chitinophagaceae at the family level, and of Flavihumibacter, Ramlibacter and Microvirga at the genus level, were all siginificant increased. Specially, Tsukamurella tyrosinosolvens were only detected in the rhizosphere of the inoculated group. This study not only founded growth-promoting properties of T. tyrosinosolvens P9 strain and its possible phosphate solublizing mechanism, but also expected to afford an excellent strain resource in biological fertilizers.


Assuntos
Actinobacteria/classificação , Arachis/crescimento & desenvolvimento , Fosfatos de Cálcio/química , Actinobacteria/isolamento & purificação , Actinobacteria/fisiologia , Arachis/microbiologia , Carbono/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Glucose/metabolismo , Nitratos/metabolismo , Nitrogênio/metabolismo , Filogenia , Compostos de Potássio/metabolismo , Rizosfera , Microbiologia do Solo
11.
Nat Microbiol ; 6(6): 703-711, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33927381

RESUMO

Many wastewater treatment plants around the world suffer from the operational problem of foaming. This is characterized by a persistent stable foam that forms on the aeration basin, which reduces effluent quality. The foam is often stabilized by a highly hydrophobic group of Actinobacteria known as the Mycolata1. Gordonia amarae is one of the most frequently reported foaming members1. With no currently reliable method for treating foams, phage biocontrol has been suggested as an attractive treatment strategy2. Phages isolated from related foaming bacteria can destabilize foams at the laboratory scale3,4; however, no phage has been isolated that lyses G. amarae. Here, we assemble the complete genomes of G. amarae and a previously undescribed species, Gordonia pseudoamarae, to examine mechanisms that encourage stable foam production. We show that both of these species are recalcitrant to phage infection via a number of antiviral mechanisms including restriction, CRISPR-Cas and bacteriophage exclusion. Instead, we isolate and cocultivate an environmental ultrasmall epiparasitic bacterium from the phylum Saccharibacteria that lyses G. amarae and G. pseudoamarae and several other Mycolata commonly associated with wastewater foams. The application of this parasitic bacterium, 'Candidatus Mycosynbacter amalyticus', may represent a promising strategy for the biocontrol of bacteria responsible for stabilizing wastewater foams.


Assuntos
Actinobacteria/fisiologia , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Águas Residuárias/microbiologia , Actinobacteria/virologia , Bactérias/classificação , Bactérias/genética , Fenômenos Fisiológicos Bacterianos , Bacteriófagos/fisiologia , Genoma Bacteriano , Filogenia , Águas Residuárias/química
12.
PLoS One ; 16(2): e0245613, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33529190

RESUMO

Sugarcane ratoon stunting disease (RSD) caused by Leifsonia xyli subsp. xyli (Lxx) is a common destructive disease that occurs around the world. Lxx is an obligate pathogen of sugarcane, and previous studies have reported some physiological responses of RSD-affected sugarcane. However, the molecular understanding of sugarcane response to Lxx infection remains unclear. In the present study, transcriptomes of healthy and Lxx-infected sugarcane stalks and leaves were studied to gain more insights into the gene activity in sugarcane in response to Lxx infection. RNA-Seq analysis of healthy and diseased plants transcriptomes identified 107,750 unigenes. Analysis of these unigenes showed a large number of differentially expressed genes (DEGs) occurring mostly in leaves of infected plants. Sugarcane responds to Lxx infection mainly via alteration of metabolic pathways such as photosynthesis, phytohormone biosynthesis, phytohormone action-mediated regulation, and plant-pathogen interactions. It was also found that cell wall defense pathways and protein phosphorylation/dephosphorylation pathways may play important roles in Lxx pathogeneis. In Lxx-infected plants, significant inhibition in photosynthetic processes through large number of differentially expressed genes involved in energy capture, energy metabolism and chloroplast structure. Also, Lxx infection caused down-regulation of gibberellin response through an increased activity of DELLA and down-regulation of GID1 proteins. This alteration in gibberellic acid response combined with the inhibition of photosynthetic processes may account for the majority of growth retardation occurring in RSD-affected plants. A number of genes associated with plant-pathogen interactions were also differentially expressed in Lxx-infected plants. These include those involved in secondary metabolite biosynthesis, protein phosphorylation/dephosphorylation, cell wall biosynthesis, and phagosomes, implicating an active defense response to Lxx infection. Considering the fact that RSD occurs worldwide and a significant cause of sugarcane productivity, a better understanding of Lxx resistance-related processes may help develop tools and technologies for producing RSD-resistant sugarcane varieties through conventional and/or molecular breeding.


Assuntos
Actinobacteria/fisiologia , Infecções por Bactérias Gram-Positivas/genética , Interações Hospedeiro-Patógeno/genética , Doenças das Plantas/genética , Saccharum/genética , Saccharum/microbiologia , Transcriptoma , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Infecções por Bactérias Gram-Positivas/microbiologia , Fotossíntese/genética , Doenças das Plantas/microbiologia , Folhas de Planta/genética , Folhas de Planta/microbiologia , RNA de Plantas/genética , RNA de Plantas/isolamento & purificação , RNA-Seq , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Saccharum/metabolismo , Transdução de Sinais/genética
13.
Arch Microbiol ; 203(4): 1367-1374, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33386868

RESUMO

An alkaliphilic actinomycete, designated HAJB-30 T, was isolated from a soda alkali-saline soil in Heilongjiang, Northeast China. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain HAJB-30 T was most closely related to type strains of the genus Phytoactinopolyspora with sequence similarities ranging between 93.5 and 98.9%. Strain HAJB-30 T grew at pH 8.0-11.0 (optimum pH 9.5-10.0) and in the presence of 0-7.0% NaCl (optimum 1.0-3.0%). Whole-cell hydrolysates of the isolate contained LL-diaminopimelic acid as the diagnostic diamino acid and mannose and rhamnose as diagnostic sugars. The major fatty acids identified were iso-C14:0, iso-C15:0, anteiso-C15:0, iso-C16:0 and anteiso-C17:0, while the menaquinone was MK-9(H4). The genome (6,589,901 bp), composed of 50 contigs, had a G + C content of 66.8%. Out of the 6074 predicted genes, 6020 were protein-coding genes, and 54 were ncRNAs. Digital DNA-DNA hybridization (dDDH) estimation and average nucleotide identity (ANI) of strain HAJB-30 T against genomes of the type strains of related species in the same family ranged between 19.7 and 22.0% and between 71.5 and 76.8%, respectively. From these results, it was concluded that strain HAJB-30 T possesses sufficient characteristics differentiated from all recognized Phytoactinopolyspora species, it is considered to be a novel species for which the name Phytoactinopolyspora limicola sp. nov. is proposed. The type strain is HAJB-30 T (= CGMCC 4.7591 T, = JCM 33694 T).


Assuntos
Actinobacteria/classificação , Actinobacteria/fisiologia , Microbiologia do Solo , Actinobacteria/química , Actinobacteria/genética , Composição de Bases , DNA Bacteriano/genética , Ácido Diaminopimélico/análise , Ácidos Graxos/análise , Genoma Fúngico/genética , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Solo/química , Açúcares/análise , Vitamina K 2/análise
14.
J Microbiol ; 59(4): 360-368, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33496938

RESUMO

Three novel bacterial strains, HDW9AT, HDW9BT, and HDW9CT, isolated from the intestine of the diving beetles Cybister lewisianus and Cybister brevis, were characterized as three novel species using a polyphasic approach. The isolates were Gram-staining-positive, strictly aerobic, non-motile, and rod-shaped. They grew optimally at 30°C (pH 7) in the presence of 0.5% (wt/vol) NaCl. Phylogenetic analysis based on the 16S rRNA gene sequences revealed that they belong to the genus Leucobacter and are closely related to L. denitrificans M1T8B10T (98.4-98.7% sequence similarity). Average nucleotide identity (ANI) values among the isolates were 76.4-84.1%. ANI values for the isolates and the closest taxonomic species, L. denitrificans KACC 14055T, were 72.3-73.1%. The isolates showed ANI values of < 76.5% with all analyzable Leucobacter strains in the EzBioCloud database. The genomic DNA G + C content of the isolates was 60.3-62.5%. The polar lipid components were phosphatidylglycerol, diphosphatidylglycerol, and other unidentified glycolipids, phospholipids, and lipids. The major cellular fatty acids were anteiso-C15:0, iso-C16:0, and anteiso-C17:0. MK-10 was the major respiratory quinone, and MK-7 and MK-11 were the minor respiratory quinones. The whole-cell sugar components of the isolates were ribose, glucose, galactose, and mannose. The isolates harbored L-2,4-diaminobutyric acid, L-serine, L-lysine, L-aspartic acid, glycine, and D-glutamic acid within the cell wall peptidoglycan. Based on phylogenetic, phenotypic, chemotaxonomic, and genotypic analyses, strains HDW9AT, HDW9BT, and HDW9CT represent three novel species within the genus Leucobacter. We propose the name Leucobacter coleopterorum sp. nov. for strain HDW9AT (= KACC 21331T = KCTC 49317T = JCM 33667T), the name Leucobacter insecticola sp. nov. for strain HDW9BT (= KACC 21332T = KCTC 49318T = JCM 33668T), and the name Leucobacter viscericola sp. nov. for strain HDW9CT (= KACC 21333T = KCTC 49319T = JCM 33669T).


Assuntos
Actinobacteria/classificação , Besouros/microbiologia , Filogenia , Actinobacteria/isolamento & purificação , Actinobacteria/fisiologia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , DNA Bacteriano/genética , Ácidos Graxos/química , Intestinos/microbiologia , Peptidoglicano/química , RNA Ribossômico 16S/genética , Vitamina K 2/química
15.
J Appl Microbiol ; 130(5): 1508-1522, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33010096

RESUMO

AIMS: This study aimed to isolate actinomycetes from marine environments and examine their antifungal activity against Talaromyces marneffei both in vitro and in vivo. METHODS AND RESULTS: Nineteen out of 101 actinomycete extracts were active and further determined for their minimum inhibitory concentrations (MIC). Three extracts of AMA50 that isolated from sediment showed strong antifungal activity against T. marneffei yeast (MICs ≤0·03-0·25 µg ml-1 ) and mould (MICs 0·5-16 µg ml-1 ) forms. The hexane extract from the cells of AMA50 (AMA50CH) exhibited the best activity against both the forms (MIC ≤ 1 µg ml-1 ). Three extracts from AMA50 killed the melanized yeast cells at 0·5 µg ml-1 . The AMA50CH was further tested for protective effects in Caenorhabditis elegans model. At concentrations of 1-8 µg ml-1 , the AMA50CH prolonged survival of T. marneffei-infected C. elegans with a 60-70% survival rate. The composition of AMA50CH was determined by gas chromatography-mass spectrometry. The major components were n-hexadecanoic acid, tetradecanoic acid and pentadecanoic acid. Sequencing analysis revealed that isolate AMA50 belonged to the genus Streptomyces. CONCLUSIONS: The AMA50CH from Streptomyces sp. AMA50 was the most effective extract against T. marneffei. SIGNIFICANCE AND IMPACT OF THE STUDY: Talaromyces marneffei is one of the most important thermally dimorphic pathogenic fungi. These results indicated the potency of marine-derived actinomycete extracts against T. marneffei both in vitro and in vivo.


Assuntos
Actinobacteria/fisiologia , Antibiose , Antifúngicos/farmacologia , Talaromyces/efeitos dos fármacos , Talaromyces/fisiologia , Actinobacteria/química , Actinobacteria/isolamento & purificação , Animais , Antifúngicos/isolamento & purificação , Antifúngicos/toxicidade , Organismos Aquáticos/microbiologia , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/microbiologia , Sedimentos Geológicos/microbiologia , Testes de Sensibilidade Microbiana , Talaromyces/ultraestrutura
16.
Biomolecules ; 10(12)2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33333896

RESUMO

The use of actinomycetes for improving soil fertility and plant production is an attractive strategy for developing sustainable agricultural systems due to their effectiveness, eco-friendliness, and low production cost. Out of 17 species isolated from the soil rhizosphere of legume crops, 4 bioactive isolates were selected and their impact on 5 legumes: soybean, kidney bean, chickpea, lentil, and pea were evaluated. According to the morphological and molecular identification, these isolates belong to the genus Streptomyces. Here, we showed that these isolates increased soil nutrients and organic matter content and improved soil microbial populations. At the plant level, soil enrichment with actinomycetes increased photosynthetic reactions and eventually increased legume yield. Actinomycetes also increased nitrogen availability in soil and legume tissue and seeds, which induced the activity of key nitrogen metabolizing enzymes, e.g., glutamine synthetase, glutamate synthase, and nitrate reductase. In addition to increased nitrogen-containing amino acids levels, we also report high sugar, organic acids, and fatty acids as well as antioxidant phenolics, mineral, and vitamins levels in actinomycete treated legume seeds, which in turn improved their seed quality. Overall, this study shed the light on the impact of actinomycetes on enhancing the quality and productivity of legume crops by boosting the bioactive primary and secondary metabolites. Moreover, our findings emphasize the positive role of actinomycetes in improving the soil by enriching its microbial population. Therefore, our data reinforce the usage of actinomycetes as biofertilizers to provide sustainable food production and achieve biosafety.


Assuntos
Actinobacteria/fisiologia , Fabaceae/crescimento & desenvolvimento , Nitrogênio/metabolismo , Sementes/fisiologia , Solo , Actinobacteria/isolamento & purificação , Actinobacteria/ultraestrutura , Aminoácidos/análise , Ácidos Graxos/análise , Fotossíntese , Filogenia , RNA Ribossômico 16S/genética , Rizosfera
17.
PLoS One ; 15(12): e0234893, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33382695

RESUMO

Breast cancer is the second leading cause of cancer-related mortality in women. Various nutritional compounds possess anti-carcinogenic properties which may be mediated through their effects on the gut microbiota and its production of short-chain fatty acids (SCFAs) for the prevention of breast cancer. We evaluated the impact of broccoli sprouts (BSp), green tea polyphenols (GTPs) and their combination on the gut microbiota and SCFAs metabolism from the microbiota in Her2/neu transgenic mice that spontaneously develop estrogen receptor-negative [ER(-)] mammary tumors. The mice were grouped based on the dietary treatment: control, BSp, GTPs or their combination from beginning in early life (BE) or life-long from conception (LC). We found that the combination group showed the strongest inhibiting effect on tumor growth volume and a significant increase in tumor latency. BSp treatment was integrally more efficacious than the GTPs group when compared to the control group. There was similar clustering of microbiota of BSp-fed mice with combination-fed mice, and GTPs-fed mice with control-fed mice at pre-tumor in the BE group and at pre-tumor and post-tumor in the LC group. The mice on all dietary treatment groups incurred a significant increase of Adlercreutzia, Lactobacillus genus and Lachnospiraceae, S24-7 family in the both BE and LC groups. We found no change in SCFAs levels in the plasma of BSp-fed, GTPs-fed and combination-fed mice of the BE group. Marked changes were observed in the mice of the LC group consisting of significant increases in propionate and isobutyrate in GTPs-fed and combination-fed mice. These studies indicate that nutrients such as BSp and GTPs differentially affect the gut microbial composition in both the BE and LC groups and the key metabolites (SCFAs) levels in the LC group. The findings also suggest that temporal factors related to different time windows of consumption during the life-span can have a promising influence on the gut microbial composition, SCFAs profiles and ER(-) breast cancer prevention.


Assuntos
Dieta/métodos , Ácidos Graxos Voláteis/sangue , Microbioma Gastrointestinal/efeitos dos fármacos , Neoplasias Mamárias Experimentais/prevenção & controle , Polifenóis/farmacologia , Plântula/química , Actinobacteria/efeitos dos fármacos , Actinobacteria/isolamento & purificação , Actinobacteria/fisiologia , Animais , Brassica/química , Clostridiales/efeitos dos fármacos , Clostridiales/isolamento & purificação , Clostridiales/fisiologia , Feminino , Microbioma Gastrointestinal/fisiologia , Expressão Gênica , Lactobacillus/efeitos dos fármacos , Lactobacillus/isolamento & purificação , Lactobacillus/fisiologia , Glândulas Mamárias Animais/efeitos dos fármacos , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/patologia , Neoplasias Mamárias Experimentais/sangue , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Knockout , Polifenóis/química , Receptor ErbB-2/deficiência , Receptor ErbB-2/genética , Receptores de Estrogênio/deficiência , Receptores de Estrogênio/genética , Chá/química
18.
BMC Microbiol ; 20(1): 300, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33023493

RESUMO

BACKGROUND: Numerous studies have reported the health-promoting effects of exopolysaccharides (EPSs) in in vitro models; however, a functional evaluation of EPSs will provide additional knowledge of EPS-microbe interactions by in vivo intestinal microbial model. In the present study, high-throughput amplicon sequencing, short-chain fatty acid (SCFAs) and intestinal inflammation evaluation were performed to explore the potential benefits of exopolysaccharides (EPSs) and EPS-producing Lactobacillus (HNUB20 group) using the healthy zebrafish (Danio rerio) model. RESULTS: The results based on microbial taxonomic analysis revealed that the abundance of four genera, Ochrobactrum, Sediminibacterium, Sphingomonas and Sphingobium, were increased in the control group in comparison to HNUB20 group. Pelomonas spp. levels were significantly higher and that of the genera Lactobacillus and Brachybacterium were significantly decreased in EPS group compared with control group. PICRUSt based functional prediction of gut microbiota metabolic pathways indicated that significantly lower abundance was found for transcription, and membrane transport, whereas folding, sorting and degradation and energy metabolism had significantly higher abundance after HNUB20 treatment. Two metabolic pathways, including metabolism and endocrine functions, were more abundant in the EPS group than control group. Similar to the HNUB20 group, transcription was also decreased in the EPS group compared with the control group. However, SCFAs and immune indexes indicated EPS and HNUB20 performed limited efficacy in the healthy zebrafish. CONCLUSIONS: The present intestinal microbial model-based study indicated that EPSs and high-yield EPS-producing Lactobacillus can shake the structure of intestinal microbiota, but cannot change SCFAs presence and intestinal inflammation.


Assuntos
Microbioma Gastrointestinal/fisiologia , Intestinos/microbiologia , Lactobacillus/fisiologia , Polissacarídeos Bacterianos/farmacologia , Peixe-Zebra/microbiologia , Actinobacteria/fisiologia , Animais , Bacteroidetes/fisiologia , Comamonadaceae/fisiologia , Ácidos Graxos Voláteis/metabolismo , Feminino , Masculino , Redes e Vias Metabólicas/genética , Ochrobactrum/fisiologia , Polissacarídeos Bacterianos/biossíntese , Sphingomonadaceae/fisiologia , Sphingomonas/fisiologia , Transcrição Genética
19.
Proc Natl Acad Sci U S A ; 117(38): 23802-23806, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32868430

RESUMO

The bacterial pathogen Pseudomonas tolaasii severely damages white button mushrooms by secretion of the pore-forming toxin tolaasin, the main virulence factor of brown blotch disease. Yet, fungus-associated helper bacteria of the genus Mycetocola (Mycetocola tolaasinivorans and Mycetocola lacteus) may protect their host by an unknown detoxification mechanism. By a combination of metabolic profiling, imaging mass spectrometry, structure elucidation, and bioassays, we found that the helper bacteria inactivate tolaasin by linearizing the lipocyclopeptide. Furthermore, we found that Mycetocola spp. impair the dissemination of the pathogen by cleavage of the lactone ring of pseudodesmin. The role of pseudodesmin as a major swarming factor was corroborated by identification and inactivation of the corresponding biosynthetic gene cluster. Activity-guided fractionation of the Mycetocola proteome, matrix-assisted laser desorption/ionization (MALDI) analyses, and heterologous enzyme production identified the lactonase responsible for toxin cleavage. We revealed an antivirulence strategy in the context of a tripartite interaction that has high ecological and agricultural relevance.


Assuntos
Actinobacteria , Agaricus , Proteínas de Bactérias , Depsipeptídeos , Pseudomonas , Fatores de Virulência , Actinobacteria/química , Actinobacteria/enzimologia , Actinobacteria/fisiologia , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Depsipeptídeos/química , Depsipeptídeos/metabolismo , Lipopeptídeos/química , Lipopeptídeos/metabolismo , Proteoma , Pseudomonas/química , Pseudomonas/patogenicidade , Fatores de Virulência/química , Fatores de Virulência/metabolismo
20.
PLoS Pathog ; 16(9): e1008800, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32913361

RESUMO

Soil-dwelling animals are at risk of pathogen infection in soils. When choosing nesting sites, animals could reduce this risk by avoiding contact with pathogens, yet there is currently little evidence. We tested this hypothesis using Solenopsis invicta as a model system. Newly mated queens of S. invicta were found to nest preferentially in soil containing more actinobacteria of Streptomyces and Nocardiopsis and to be attracted to two volatiles produced by these bacteria, geosmin and 2-methylisoborneol. Actinobacteria-rich soil was favored by S. invicta and this soil contained fewer putative entomopathogenic fungi than adjacent areas. Queens in such soil benefited from a higher survival rate. In culture, isolated actinobacteria inhibited entomopathogenic fungi, suggested that their presence may reduce the risk of fungal infection. These results indicated a soil-dwelling ant may choose nest sites presenting relatively low pathogen risk by detecting the odors produced by bacteria with anti-fungal properties.


Assuntos
Actinobacteria/fisiologia , Anti-Infecciosos/farmacologia , Formigas/fisiologia , Fungos/efeitos dos fármacos , Micoses/prevenção & controle , Comportamento de Nidação/efeitos dos fármacos , Compostos Orgânicos Voláteis/farmacologia , Animais , Formigas/microbiologia , Micoses/microbiologia , Microbiologia do Solo , Simbiose
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