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1.
Science ; 373(6556)2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34385369

RESUMO

Capturing the heterogeneous phenotypes of microbial populations at relevant spatiotemporal scales is highly challenging. Here, we present par-seqFISH (parallel sequential fluorescence in situ hybridization), a transcriptome-imaging approach that records gene expression and spatial context within microscale assemblies at a single-cell and molecule resolution. We applied this approach to the opportunistic pathogen Pseudomonas aeruginosa, analyzing about 600,000 individuals across dozens of conditions in planktonic and biofilm cultures. We identified numerous metabolic- and virulence-related transcriptional states that emerged dynamically during planktonic growth, as well as highly spatially resolved metabolic heterogeneity in sessile populations. Our data reveal that distinct physiological states can coexist within the same biofilm just several micrometers away, underscoring the importance of the microenvironment. Our results illustrate the complex dynamics of microbial populations and present a new way of studying them at high resolution.


Assuntos
Pseudomonas aeruginosa/genética , Transcriptoma , Biofilmes/crescimento & desenvolvimento , Proteínas de Fímbrias/genética , Flagelina/genética , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Hibridização in Situ Fluorescente , Fenótipo , Plâncton/genética , Plâncton/crescimento & desenvolvimento , Plâncton/metabolismo , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/patogenicidade , Piocinas/biossíntese , RNA Bacteriano/genética , RNA Bacteriano/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Célula Única , Análise Espaço-Temporal , Virulência/genética
2.
Molecules ; 26(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34443617

RESUMO

The present study is focused on the effect of biofilm medium chemistry on oxalate crystallization and contributes to the study of the patterns of microbial biomineralization and the development of nature-like technologies, using the metabolism of microscopic fungi. Calcium oxalates (weddellite and whewellite in different ratios) were synthesized by chemical precipitation in a weakly acidic environment (pH = 4-6), as is typical for the stationary phase of micromycetes growth, with a ratio of Ca2+/C2O42- = 4.0-5.5, at room temperature. Additives, which are common for biofilms on the surface of stone in an urban environment (citric, malic, succinic and fumaric acids; and K+, Mg2+, Fe3+, Sr2+, SO42+, PO43+ and CO32+ ions), were added to the solutions. The resulting precipitates were studied via X-ray powder diffraction (XRPD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDXS). It was revealed that organic acids, excreted by micromicetes, and some environmental ions, as well as their combinations, significantly affect the weddellite/whewellite ratio and the morphology of their phases (including the appearance of tetragonal prism faces of weddellite). The strongest unique effect leading to intensive crystallization of weddellite was only caused by the presence of citric acid additive in the medium. Minor changes in the composition of the additive components can lead to significant changes in the weddellite/whewellite ratio. The effect of the combination of additives on this ratio does not obey the law of additivity. The content of weddellite in the systems containing a representative set of both organic acids and environmental ions is ~20 wt%, which is in good agreement with natural systems.


Assuntos
Biofilmes/crescimento & desenvolvimento , Oxalato de Cálcio/química , Cristalização , Concentração de Íons de Hidrogênio
3.
Molecules ; 26(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34361723

RESUMO

Genito-urinary tract infections have a high incidence in the general population, being more prevalent among women than men. These diseases are usually treated with antibiotics, but very frequently, they are recurrent and lead to the creation of resistance and are associated with increased morbidity and mortality. For this reason, it is necessary to develop new compounds for their treatment. In this work, our objective is to review the characteristics of the compounds of a new formulation called Itxasol© that is prescribed as an adjuvant for the treatment of UTIs and composed of ß-arbutin, umbelliferon and n-acetyl cysteine. This formulation, based on biomimetic principles, makes Itxasol© a broad-spectrum antibiotic with bactericidal, bacteriostatic and antifungal properties that is capable of destroying the biofilm and stopping its formation. It also acts as an anti-inflammatory agent, without the adverse effects associated with the recurrent use of antibiotics that leads to renal nephrotoxicity and other side effects. All these characteristics make Itxasol© an ideal candidate for the treatment of UTIs since it behaves like an antibiotic and with better characteristics than other adjuvants, such as D-mannose and cranberry extracts.


Assuntos
Acetilcisteína/uso terapêutico , Arbutina/uso terapêutico , Produtos Biológicos/uso terapêutico , Umbeliferonas/uso terapêutico , Infecções Urinárias/tratamento farmacológico , Acetilcisteína/química , Antibacterianos/química , Antibacterianos/uso terapêutico , Anti-Inflamatórios/química , Anti-Inflamatórios/uso terapêutico , Antifúngicos/química , Antifúngicos/uso terapêutico , Arbutina/química , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Produtos Biológicos/química , Materiais Biomiméticos/química , Materiais Biomiméticos/uso terapêutico , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Candida/patogenicidade , Combinação de Medicamentos , Feminino , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Negativas/patogenicidade , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Bactérias Gram-Positivas/patogenicidade , Humanos , Masculino , Testes de Sensibilidade Microbiana , Umbeliferonas/química , Infecções Urinárias/microbiologia , Infecções Urinárias/patologia
4.
Molecules ; 26(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34443332

RESUMO

Peptoids (oligo N-substituted glycines) are peptide analogues, which can be designed to mimic host antimicrobial peptides, with the advantage that they are resistant to proteolytic degradation. Few studies on the antimicrobial efficacy of peptoids have focused on Gram negative anaerobic microbes associated with clinical infections, which are commonly recalcitrant to antibiotic treatment. We therefore studied the cytotoxicity and antibiofilm activity of a family of peptoids against the Gram negative obligate anaerobe Fusobacterium nucleatum, which is associated with infections in the oral cavity. Two peptoids, peptoid 4 (NaeNpheNphe)4 and peptoid 9 (NahNspeNspe)3 were shown to be efficacious against F. nucleatum biofilms at a concentration of 1 µM. At this concentration, peptoids 4 and 9 were not cytotoxic to human erythrocytes or primary human gingival fibroblast cells. Peptoids 4 and 9 therefore have merit as future therapeutics for the treatment of oral infections.


Assuntos
Biofilmes/efeitos dos fármacos , Fusobacterium nucleatum/efeitos dos fármacos , Fusobacterium nucleatum/fisiologia , Peptoides/farmacologia , Biofilmes/crescimento & desenvolvimento , Farmacorresistência Bacteriana/efeitos dos fármacos
5.
Molecules ; 26(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34443363

RESUMO

The antimicrobial properties of herbs from Papaveraceae have been used in medicine for centuries. Nevertheless, mutual relationships between the individual bioactive substances contained in these plants remain poorly elucidated. In this work, phytochemical composition of extracts from the aerial and underground parts of five Papaveraceae species (Chelidonium majus L., Corydalis cava (L.) Schweigg. and Körte, C. cheilanthifolia Hemsl., C. pumila (Host) Rchb., and Fumaria vaillantii Loisel.) were examined using LC-ESI-MS/MS with a triple quadrupole analyzer. Large differences in the quality and quantity of all analyzed compounds were observed between species of different genera and also within one genus. Two groups of metabolites predominated in the phytochemical profiles. These were isoquinoline alkaloids and, in smaller amounts, non-phenolic carboxylic acids and phenolic compounds. In aerial and underground parts, 22 and 20 compounds were detected, respectively. These included: seven isoquinoline alkaloids: protopine, allocryptopine, coptisine, berberine, chelidonine, sanguinarine, and chelerythrine; five of their derivatives as well as non-alkaloids: malic acid, trans-aconitic acid, quinic acid, salicylic acid, trans-caffeic acid, p-coumaric acid, chlorogenic acid, quercetin, and kaempferol; and vanillin. The aerial parts were much richer in phenolic compounds regardless of the plant species. Characterized extracts were studied for their antimicrobial potential against planktonic and biofilm-producing cells of S. aureus, P. aeruginosa, and C. albicans. The impact of the extracts on cellular metabolic activity and biofilm biomass production was evaluated. Moreover, the antimicrobial activity of the extracts introduced to the polymeric carrier made of bacterial cellulose was assessed. Extracts of C. cheilanthifolia were found to be the most effective against all tested human pathogens. Multiple regression tests indicated a high antimicrobial impact of quercetin in extracts of aerial parts against planktonic cells of S. aureus, P. aeruginosa, and C. albicans, and no direct correlation between the composition of other bioactive substances and the results of antimicrobial activity were found. Conclusively, further investigations are required to identify the relations between recognized and unrecognized compounds within extracts and their biological properties.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Produtos Biológicos/farmacologia , Papaveraceae/química , Extratos Vegetais/farmacologia , Antibacterianos/química , Biofilmes/crescimento & desenvolvimento , Produtos Biológicos/química , Avaliação Pré-Clínica de Medicamentos , Extratos Vegetais/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia
6.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361735

RESUMO

Biofilms, the predominant growth mode of microorganisms, pose a significant risk to human health. The protective biofilm matrix, typically composed of exopolysaccharides, proteins, nucleic acids, and lipids, combined with biofilm-grown bacteria's heterogenous physiology, leads to enhanced fitness and tolerance to traditional methods for treatment. There is a need to identify biofilm inhibitors using diverse approaches and targeting different stages of biofilm formation. This review discusses discovery strategies that successfully identified a wide range of inhibitors and the processes used to characterize their inhibition mechanism and further improvement. Additionally, we examine the structure-activity relationship (SAR) for some of these inhibitors to optimize inhibitor activity.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Matriz Extracelular de Substâncias Poliméricas/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Antibacterianos/biossíntese , Antibacterianos/síntese química , Antibacterianos/isolamento & purificação , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , GMP Cíclico/antagonistas & inibidores , GMP Cíclico/química , GMP Cíclico/metabolismo , Desenho de Fármacos , Descoberta de Drogas , Farmacorresistência Bacteriana/efeitos dos fármacos , Matriz Extracelular de Substâncias Poliméricas/química , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Negativas/patogenicidade , Bactérias Gram-Positivas/crescimento & desenvolvimento , Bactérias Gram-Positivas/patogenicidade , Lipídeos/antagonistas & inibidores , Lipídeos/química , Testes de Sensibilidade Microbiana , Ácidos Nucleicos/antagonistas & inibidores , Ácidos Nucleicos/química , Ácidos Nucleicos/metabolismo , Polissacarídeos Bacterianos/antagonistas & inibidores , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/metabolismo , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/isolamento & purificação , Relação Estrutura-Atividade
7.
Viruses ; 13(7)2021 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-34372538

RESUMO

Bacterial surface structures of a proteinic nature and glycoconjugates contribute to biofilm formation and provide shields to host defense mechanisms (e.g., the complement system and phagocytosis). A loss or alteration of these molecules, leading to phage resistance, could result in fewer virulent bacteria. In this study, we evaluate the biology and phenotype changes in Pseudomonas aeruginosa PAO1 phage-resistant clones, which emerge in phage-treated biofilms. We characterize these clones for phage-typing patterns, antibiotic resistance, biofilm formation, pathogenicity, and interactions with the innate immune system. Another important question that we address is whether phage-resistant mutants are also generated incidentally, despite the phage treatment-selective pressure, as the natural adaptation of the living biofilm population. It is found that the application of different phages targeting a particular receptor selects similar phage resistance patterns. Nevertheless, this results in a dramatic increase in the population heterogeneity, giving over a dozen phage-typing patterns, compared to one of the untreated PAO1 sessile forms. We also confirm the hypothesis that "phage-resistant bacteria are more susceptible to antibiotics and host-clearance mechanisms by the immune system". These findings support phage application in therapy, although the overall statement that phage treatment selects the less virulent bacterial population should be further verified using a bigger collection of clinical strains.


Assuntos
Resistência Microbiana a Medicamentos/genética , Fagos de Pseudomonas/genética , Pseudomonas aeruginosa/virologia , Antibacterianos/farmacologia , Bacteriófagos/genética , Biofilmes/crescimento & desenvolvimento , Resistência Microbiana a Medicamentos/fisiologia , Humanos , Terapia por Fagos/métodos , Fagocitose/genética , Fenótipo , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Virulência
8.
Molecules ; 26(16)2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34443301

RESUMO

Staphylococcus saprophyticus, the food-borne bacteria present in dairy products, ready-to-eat food and environmental sources, has been reported with antibiotic resistance, raising concerns about food microbial safety. The antimicrobial resistance of S. saprophyticus requires the development of new strategies. Light- and photosensitizer-based antimicrobial photodynamic inactivation (PDI) is a promising approach to control microbial contamination, whereas there is limited information regarding the effectiveness of PDI on S. saprophyticus biofilm control. In this study, PDI mediated by natural bioactive compound (curcumin) associated with LED was evaluated for its potential to prevent and disrupt S. saprophyticus biofilms. Biofilms were treated with curcumin (50, 100, 200 µM) and LED fluence (4.32 J/cm2, 8.64 J/cm2, 17.28 J/cm2). Control groups included samples treated only with curcumin or light, and samples received neither curcumin nor light. The action was examined on biofilm mass, viability, cellular metabolic activity and cytoplasmic membrane integrity. PDI using curcumin associated with LED exhibited significant antibiofilm activities, inducing biofilm prevention and removal, metabolic inactivation, intracellular membrane damage and cell death. Likewise, scanning electronic microscopy observations demonstrated obvious structural injury and morphological alteration of S. saprophyticus biofilm after PDI application. In conclusion, curcumin is an effective photosensitizer for the photodynamic control of S. saprophyticus biofilm.


Assuntos
Biofilmes/crescimento & desenvolvimento , Produtos Biológicos/farmacologia , Fotoquimioterapia , Staphylococcus saprophyticus/fisiologia , Biofilmes/efeitos dos fármacos , Contagem de Colônia Microbiana , Curcumina/farmacologia , Staphylococcus saprophyticus/citologia , Staphylococcus saprophyticus/efeitos dos fármacos , Staphylococcus saprophyticus/ultraestrutura
9.
Int J Mol Sci ; 22(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34445108

RESUMO

Atopic dermatitis (AD) is a common inflammatory dermatosis affecting up to 30% of children and 10% of adults worldwide. AD is primarily driven by an epidermal barrier defect which triggers immune dysregulation within the skin. According to recent research such phenomena are closely related to the microbial dysbiosis of the skin. There is growing evidence that cutaneous microbiota and bacterial biofilms negatively affect skin barrier function, contributing to the onset and exacerbation of AD. This review summarizes the latest data on the mechanisms leading to microbiome dysbiosis and biofilm formation in AD, and the influence of these phenomena on skin barrier function.


Assuntos
Bactérias/imunologia , Biofilmes/crescimento & desenvolvimento , Dermatite Atópica/imunologia , Disbiose/imunologia , Epiderme/imunologia , Microbiota/imunologia , Animais , Disbiose/microbiologia , Humanos , Pele/imunologia
10.
Int J Mol Sci ; 22(16)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34445281

RESUMO

Bacterial quorum sensing (QS) is a cell-cell communication system that regulates several bacterial mechanisms, including the production of virulence factors and biofilm formation. Thus, targeting microbial QS is seen as a plausible alternative strategy to antibiotics, with potentiality to combat multidrug-resistant pathogens. Many phytochemicals with QS interference activity are currently being explored. Herein, an extract and a compound of bioinspired origin were tested for their ability to inhibit biofilm formation and interfere with the expression of QS-related genes in Pseudomonas aeruginosa and Staphylococcus aureus. The extract, a carboxypyranoanthocyanins red wine extract (carboxypyrano-ant extract), and the pure compound, carboxypyranocyanidin-3-O-glucoside (carboxypyCy-3-glc), did not cause a visible effect on the biofilm formation of the P. aeruginosa biofilms; however, both significantly affected the formation of biofilms by the S. aureus strains, as attested by the crystal violet assay and fluorescence microscopy. Both the extract and the pure compound significantly interfered with the expression of several QS-related genes in the P. aeruginosa and S. aureus biofilms, as per reverse transcription-quantitative polymerase chain reaction (RT-qPCR) results. Indeed, it was possible to conclude that these molecules interfere with QS at distinct stages and in a strain-specific manner. An extract with anti-QS properties could be advantageous because it is easily obtained and could have broad, antimicrobial therapeutic applications if included in topical formulations.


Assuntos
Antocianinas/farmacologia , Biofilmes/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Percepção de Quorum/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Biofilmes/crescimento & desenvolvimento
11.
Int J Mol Sci ; 22(16)2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34445806

RESUMO

After the first ancient studies on microbial slime (the name by which the biofilm matrix was initially indicated), multitudes of studies on the morphology, composition and physiology of biofilms have arisen. The emergence of the role that biofilms play in the pathogenesis of recalcitrant and persistent clinical infections, such as periprosthetic orthopedic infections, has reinforced scientific interest. Extracellular DNA (eDNA) is a recently uncovered component that is proving to be almost omnipresent in the extracellular polymeric substance (EPS) of biofilm. This macromolecule is eliciting unprecedented consideration for the critical impact on the pathogenesis of chronic clinical infections. After a systematic review of the literature, an updated description of eDNA in biofilms is presented, with a special focus on the latest findings regarding its fundamental structural role and the contribution it makes to the complex architecture of bacterial biofilms through interactions with a variety of other molecular components of the biofilm matrix.


Assuntos
Bactérias/genética , Biofilmes/crescimento & desenvolvimento , DNA Bacteriano/genética , Matriz Extracelular de Substâncias Poliméricas/genética , Animais , Proteínas de Bactérias/genética , Humanos
12.
J Med Microbiol ; 70(8)2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34338626

RESUMO

Introduction. Biofilm formation is a major virulence factor associated with Staphylococcus aureus infections. However, the influence of plasma proteins on biofilm formation of clinical isolates in vitro remains unclear.Hypotheses. We hypothesized that coating surfaces with plasma proteins might induce biofilm formation by S. aureus of different clonal lineages.Aim. To evaluate biofilm production by clinical S. aureus isolates of different clonal lineages isolated in Rio de Janeiro hospitals and investigated the presence of biofilm-associated genes.Methodology. This study assessed biofilm production of 60 S. aureus isolates in polystyrene microtitre plates with and without fibrinogen or fibronectin. The biochemical composition of the biofilm matrices was determined and the biofilm formation on fibrinogen-coated surfaces was also evaluated by confocal laser scanning microscopy. The presence of biofilm-related genes was detected by PCR, and the typing and functionality of agr operon was also evaluated.Results. Most of the isolates (45 %) were weak biofilm producers or non-producers. However, most of them presented a significant increase in biofilm production on plates covered with plasma proteins. There was no significant difference in biofilm formation between methicillin-resistant and -susceptible S. aureus isolates, or between different clonal lineages, except for ST30-IV (weak producers) and ST239-III (strong producers). The fnbB gene was associated with higher biofilm production.Conclusion. An increase in biofilm production in the presence of plasma proteins highlights the importance of investigating biofilm formation by S. aureus clinical isolates under different conditions since this virulence factor contributes to persistent infections and increased resistance to antimicrobials.


Assuntos
Biofilmes/crescimento & desenvolvimento , Fibrinogênio , Fibronectinas , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Staphylococcus aureus/patogenicidade , Adesinas Bacterianas/genética , Aderência Bacteriana/genética , Proteínas de Bactérias/genética , Genes Bacterianos , Genótipo , Humanos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/fisiologia , Óperon , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/fisiologia , Transativadores/genética
13.
NPJ Biofilms Microbiomes ; 7(1): 54, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34210981

RESUMO

Biofilm and nitrogen fixation are two competitive strategies used by many plant-associated bacteria; however, the mechanisms underlying the formation of nitrogen-fixing biofilms remain largely unknown. Here, we examined the roles of multiple signalling systems in the regulation of biofilm formation by root-associated diazotrophic P. stutzeri A1501. Physiological analysis, construction of mutant strains and microscale thermophoresis experiments showed that RpoN is a regulatory hub coupling nitrogen fixation and biofilm formation by directly activating the transcription of pslA, a major gene involved in the synthesis of the Psl exopolysaccharide component of the biofilm matrix and nifA, the transcriptional activator of nif gene expression. Genetic complementation studies and determination of the copy number of transcripts by droplet digital PCR confirmed that the regulatory ncRNA RsmZ serves as a signal amplifier to trigger biofilm formation by sequestering the translational repressor protein RsmA away from pslA and sadC mRNAs, the latter of which encodes a diguanylate cyclase that synthesises c-di-GMP. Moreover, RpoS exerts a braking effect on biofilm formation by transcriptionally downregulating RsmZ expression, while RpoS expression is repressed posttranscriptionally by RsmA. These findings provide mechanistic insights into how the Rpo/Gac/Rsm regulatory networks fine-tune nitrogen-fixing biofilm formation in response to the availability of nutrients.


Assuntos
Proteínas de Bactérias/genética , Biofilmes/crescimento & desenvolvimento , Regulação Bacteriana da Expressão Gênica , Redes Reguladoras de Genes , Fixação de Nitrogênio , Pseudomonas stutzeri/fisiologia , Proteínas de Bactérias/metabolismo , Ordem dos Genes , Nitrogenase/genética , Nitrogenase/metabolismo , Sequências Repetitivas de Ácido Nucleico , Ativação Transcricional
14.
Int J Mol Sci ; 22(14)2021 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-34299026

RESUMO

Pseudomonas aeruginosa and Sphingobacterium sp. are well known for their ability to decontaminate many environmental pollutants while Geobacillus sp. have been exploited for their thermostable enzymes. This study reports the annotation of genomes of P. aeruginosa S3, Sphingobacterium S2 and Geobacillus EC-3 that were isolated from compost, based on their ability to degrade poly(lactic acid), PLA. Draft genomes of the strains were assembled from Illumina reads, annotated and viewed with the aim of gaining insight into the genetic elements involved in degradation of PLA. The draft genome of Sphinogobacterium strain S2 (435 contigs) was estimated at 5,604,691 bp and the draft genome of P. aeruginosa strain S3 (303 contigs) was estimated at 6,631,638 bp. The draft genome of the thermophile Geobacillus strain EC-3 (111 contigs) was estimated at 3,397,712 bp. A total of 5385 (60% with annotation), 6437 (80% with annotation) and 3790 (74% with annotation) protein-coding genes were predicted for strains S2, S3 and EC-3, respectively. Catabolic genes for the biodegradation of xenobiotics, aromatic compounds and lactic acid as well as the genes attributable to the establishment and regulation of biofilm were identified in all three draft genomes. Our results reveal essential genetic elements that facilitate PLA metabolism at mesophilic and thermophilic temperatures in these three isolates.


Assuntos
Proteínas de Bactérias/genética , Biofilmes/crescimento & desenvolvimento , Genoma Bacteriano , Geobacillus/genética , Poliésteres/metabolismo , Pseudomonas aeruginosa/genética , Sphingobacterium/genética , Biodegradação Ambiental , DNA Bacteriano/análise , DNA Bacteriano/genética , Sequenciamento de Nucleotídeos em Larga Escala , Anotação de Sequência Molecular , Filogenia
15.
NPJ Biofilms Microbiomes ; 7(1): 56, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215744

RESUMO

Aryl polyenes (APEs) are specialized polyunsaturated carboxylic acids that were identified in silico as the product of the most widespread family of bacterial biosynthetic gene clusters (BGCs). They are present in several Gram-negative host-associated bacteria, including multidrug-resistant human pathogens. Here, we characterize a biological function of APEs, focusing on the BGC from a uropathogenic Escherichia coli (UPEC) strain. We first perform a genetic deletion analysis to identify the essential genes required for APE biosynthesis. Next, we show that APEs function as fitness factors that increase protection from oxidative stress and contribute to biofilm formation. Together, our study highlights key steps in the APE biosynthesis pathway that can be explored as potential drug targets for complementary strategies to reduce fitness and prevent biofilm formation of multi-drug resistant pathogens.


Assuntos
Biofilmes , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Genes Essenciais , Polienos/metabolismo , Biofilmes/crescimento & desenvolvimento , Transporte Biológico , Vias Biossintéticas , Regulação Bacteriana da Expressão Gênica , Estrutura Molecular , Mutação , Oxirredução , Fenótipo , Polienos/química
16.
Molecules ; 26(14)2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34299385

RESUMO

An efficient and simple protocol for the synthesis of a new class of diverse bis(indolyl)pyridines analogues of the marine alkaloid nortopsentin has been reported. A one-pot four-component condensation of 3-cyanocarbomethylindole, various aldehyde, 3-acetylindole, and ammonium acetate in glacial acetic acid led to the formation of 2,6-bis(1H-indol-3-yl)-4-(substituted-phenyl)pyridine-5-carbonitriles. Additionally, 2,6-bis(1H-indol-3-yl)-4-(benzofuran) pyridine-5-carbonitriles were prepared via a one-pot four-component condensation of 3-cyanocarbomethylindole, various N-substituted-indole-3-aldehydes, 2-acetylbenzofuran, and ammonium acetate. The synthesized compounds were evaluated for their ability to inhibit biofilm formation against the Gram-positive bacterial reference strains Staphylococcus aureus ATCC 6538 and the Gram-negative strain Escherichia coli ATCC 25922. Some of the new compounds showed a marked selectivity against the Gram-positive and Gram-negative strains. Remarkably, five compounds 4b, 7a, 7c, 7d and 8e demonstrated good antibiofilm formation against S. aureus and E. coli. On the other hand, the release of reducing sugars and proteins from the treated bacterial strains over the untreated strains was considered to explain the disruption effect of the selected compound on the contact cells of S. aureus and E. coli. Out of all studied compounds, the binding energies and binding mode of bis-indole derivatives 7c and 7d were theoretically the best thymidylate kinase, DNA gyrase B and DNA topoisomerase IV subunit B inhibitors.


Assuntos
Alcaloides/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Inibidores Enzimáticos/farmacologia , Indóis/química , Biofilmes/efeitos dos fármacos , DNA Girase/química , DNA Topoisomerase IV/antagonistas & inibidores , Inibidores Enzimáticos/química , Simulação de Acoplamento Molecular , Núcleosídeo-Fosfato Quinase/antagonistas & inibidores , Piridinas/química
17.
Nat Commun ; 12(1): 4613, 2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-34326342

RESUMO

R-bodies are long, extendable protein polymers formed in the cytoplasm of some bacteria; they are best known for their role in killing of paramecia by bacterial endosymbionts. Pseudomonas aeruginosa PA14, an opportunistic pathogen of diverse hosts, contains genes (referred to as the reb cluster) with potential to confer production of R-bodies and that have been implicated in virulence. Here, we show that products of the PA14 reb cluster associate with R-bodies and control stochastic expression of R-body structural genes. PA14 expresses reb genes during colonization of plant and nematode hosts, and R-body production is required for full virulence in nematodes. Analyses of nematode ribosome content and immune response indicate that P. aeruginosa R-bodies act via a mechanism involving ribosome cleavage and translational inhibition. Our observations provide insight into the biology of R-body production and its consequences during P. aeruginosa infection.


Assuntos
Proteínas de Bactérias/metabolismo , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/patogenicidade , Fatores de Virulência/metabolismo , Animais , Proteínas de Bactérias/genética , Biofilmes/crescimento & desenvolvimento , Caenorhabditis elegans , Filogenia , Infecções por Pseudomonas/genética , Infecções por Pseudomonas/metabolismo , Pseudomonas aeruginosa/citologia , Pseudomonas aeruginosa/genética , Virulência , Fatores de Virulência/genética
18.
Methods Mol Biol ; 2341: 69-78, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34264462

RESUMO

Most Staphylococcus aureus strains can grow as a multicellular biofilm, a phenotype of utmost importance to clinical infections such as endocarditis, osteomyelitis, and implanted medical device infection. As biofilms are inherently more tolerant to the host immune system and antibiotics, understanding the S. aureus genes and regulatory circuits that contribute to biofilm development is an active and on-going field of research. This chapter details a high-throughput and standardized way to grow S. aureus biofilms using a classical microtiter plate assay. Biofilms can be quantified using crystal violet or by confocal microscopy imaging and COMSTAT analysis.


Assuntos
Biofilmes/crescimento & desenvolvimento , Violeta Genciana/farmacologia , Staphylococcus aureus/fisiologia , Técnicas Bacteriológicas , Microscopia Confocal , Espectrofotometria
19.
Methods Mol Biol ; 2341: 117-125, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34264467

RESUMO

Secreted bacterial proteins are difficult to identify directly from an infection site due to a limited amount of bacteria and presence of a large quantity of host proteins. Here we describe a rat model of orthopedic implant that allows us to harvest bacterial biofilm materials sufficient for identification of bacterial proteins in the biofilm matrix by liquid chromatography-tandem MS (GeLC-MS/MS) analysis.


Assuntos
Proteínas de Bactérias/isolamento & purificação , Biofilmes/crescimento & desenvolvimento , Infecções Relacionadas à Prótese/microbiologia , Infecções Estafilocócicas/diagnóstico , Staphylococcus aureus/fisiologia , Animais , Cromatografia Líquida , Modelos Animais de Doenças , Masculino , Próteses e Implantes/microbiologia , Ratos , Staphylococcus aureus/metabolismo , Espectrometria de Massas em Tandem
20.
Methods Mol Biol ; 2341: 153-159, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34264471

RESUMO

Biofilms provide an environment in which bacteria can survive adverse conditions such as nutrient or oxygen deficiencies, and antibiotic treatments. Bacterial survival of antibiotic treatments can often result in antimicrobial resistance, which can make treating infections substantially more difficult, increase the burden of healthcare costs, and hinder the healing of infected wounds. As Staphylococcus aureus is a bacterium that commonly causes skin infections, can be found in infected skin wounds, and is prone to developing antimicrobial resistance-especially within a biofilm microenvironment, the study and development of methodologies to treat infected wounds have become an important topic of research. To study the development of bacterial biofilm in a skin wound, this chapter discusses an in vitro model to access biofilm growth in an environment that mimics a human skin wound. This model serves as a tool to study the biofilm growth and efficacy of antibiotic use in an in vitro system that more closely resembles human skin tissue, rather than a polystyrene plate.


Assuntos
Biofilmes/crescimento & desenvolvimento , Staphylococcus aureus/patogenicidade , Infecção dos Ferimentos/microbiologia , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Farmacorresistência Bacteriana , Humanos , Viabilidade Microbiana , Modelos Biológicos , Pele/microbiologia , Staphylococcus aureus/efeitos dos fármacos
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