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1.
J Fungi (Basel) ; 8(11)2022 Oct 28.
Article in English | MEDLINE | ID: mdl-36354912

ABSTRACT

Fungi are vast in terms of diversity, ecological roles, habitats they occupy, physiology, metabolism, and in many other characteristics [...].

2.
J Clin Med ; 11(19)2022 Sep 22.
Article in English | MEDLINE | ID: mdl-36233441

ABSTRACT

COVID-19 is the most impacting global pandemic of all time, with over 600 million infected and 6.5 million deaths worldwide, in addition to an unprecedented economic impact. Despite the many advances in scientific knowledge about the disease, much remains to be clarified about the molecular alterations induced by SARS-CoV-2 infection. In this work, we present a hybrid proteomics and in silico interactomics strategy to establish a COVID-19 salivary protein profile. Data are available via ProteomeXchange with identifier PXD036571. The differential proteome was narrowed down by the Partial Least-Squares Discriminant Analysis and enrichment analysis was performed with FunRich. In parallel, OralInt was used to determine interspecies Protein-Protein Interactions between humans and SARS-CoV-2. Five dysregulated biological processes were identified in the COVID-19 proteome profile: Apoptosis, Energy Pathways, Immune Response, Protein Metabolism and Transport. We identified 10 proteins (KLK 11, IMPA2, ANXA7, PLP2, IGLV2-11, IGHV3-43D, IGKV2-24, TMEM165, VSIG10 and PHB2) that had never been associated with SARS-CoV-2 infection, representing new evidence of the impact of COVID-19. Interactomics analysis showed viral influence on the host immune response, mainly through interaction with the degranulation of neutrophils. The virus alters the host's energy metabolism and interferes with apoptosis mechanisms.

3.
J Fungi (Basel) ; 8(9)2022 Sep 17.
Article in English | MEDLINE | ID: mdl-36135697

ABSTRACT

Neofusicoccum parvum is a fungal plant pathogen of a wide range of hosts but knowledge about the virulence factors of N. parvum and host-pathogen interactions is rather limited. The molecules involved in the interaction between N. parvum and Eucalyptus are mostly unknown, so we used a multi-omics approach to understand pathogen-host interactions. We present the first comprehensive characterization of the in vitro secretome of N. parvum and a prediction of protein-protein interactions using a dry-lab non-targeted interactomics strategy. We used LC-MS to identify N. parvum protein profiles, resulting in the identification of over 400 proteins, from which 117 had a different abundance in the presence of the Eucalyptus stem. Most of the more abundant proteins under host mimicry are involved in plant cell wall degradation (targeting pectin and hemicellulose) consistent with pathogen growth on a plant host. Other proteins identified are involved in adhesion to host tissues, penetration, pathogenesis, or reactive oxygen species generation, involving ribonuclease/ribotoxin domains, putative ricin B lectins, and necrosis elicitors. The overexpression of chitosan synthesis proteins during interaction with the Eucalyptus stem reinforces the hypothesis of an infection strategy involving pathogen masking to avoid host defenses. Neofusicoccum parvum has the molecular apparatus to colonize the host but also actively feed on its living cells and induce necrosis suggesting that this species has a hemibiotrophic lifestyle.

4.
PLoS One ; 17(1): e0263033, 2022.
Article in English | MEDLINE | ID: mdl-35089942

ABSTRACT

SARS-CoV-2 pandemic has forced frequent testing of populations. It is necessary to identify the most cost-effective strategies for the detection of COVID-19 outbreaks. Nasopharyngeal samples have been used for SARS-CoV-2 detection but require a healthcare professional to collect the sample and cause discomfort and pain to the individual. Saliva has been suggested as an appropriate fluid for the diagnosis of COVID-19. We have investigated the possibility of using pools of saliva samples to detect SARS-CoV-2 in symptomatic and asymptomatic patients. Two hundred and seventy-nine saliva samples were analyzed through RT-PCR of Envelope, Nucleocapsid and Open Reading Frame 1ab genes. Reproducibility assays showed an almost perfect agreement as well as high sensitivity (96.6%), specificity (96.8%), positive predicted value (96.6%), and negative predicted value (96.8%). The average Cycle Threshold of the genes detected was 29.7. No significant differences (p > 0.05) were detected when comparing the cycle threshold average of two consecutive reactions on the same positive saliva samples. Saliva samples have a higher median viral load (32.6) than in nasopharyngeal samples (28.9), although no significant differences were detected (p > 0.05). Saliva-pool samples allowed effective SARS-CoV-2 screening, with a higher sensibility (96.9%) on 10-sample pools than in 20-sample pools (87.5%). Regardless of pools size specificity was high (99.9%) and an almost perfect agreement was observed. Our strategy was successfully applied in population wide testing of more than 2000 individuals, showing that it is possible to use pooled saliva as diagnostic fluid for SARS-CoV-2 infection.


Subject(s)
COVID-19 Testing/methods , SARS-CoV-2/isolation & purification , Saliva/virology , Specimen Handling/methods , COVID-19/diagnosis , Humans , Reproducibility of Results , Sensitivity and Specificity
5.
N Biotechnol ; 60: 62-71, 2021 Jan 25.
Article in English | MEDLINE | ID: mdl-32891869

ABSTRACT

Novel natural products are urgently needed to address the worldwide incidence of bacterial resistance to antibiotics. Extreme environments are a major source of novel compounds with unusual chemical structures. Pedobacter lusitanus NL19 is a new bacterial species that was isolated from one such environment and which produces compounds with potent activity against relevant microorganisms in the clinical, food, veterinary and aquaculture areas. The production of antimicrobials by P. lusitanus NL19 was identified in tryptic soy agar (TSA), but not in its equivalent broth (TSB). It was observed that in TSB medium a high concentration of casein peptone (PC) repressed the production of antibacterial compounds. HPLC, MS and MS/MS spectra with de novo sequencing revealed that the bioactivity of P. lusitanus NL19 was due to the production of pedopeptins. Hence, biosynthesis of pedopeptins is inhibited by high concentrations of PC in the broth medium. Furthermore, a nonribosomal peptide synthetase (NRPS) gene cluster was identified in the genome of NL19 encoding the biosynthesis of the peptides. qPCR analysis confirmed that the transcription of these genes is repressed in cells cultivated in high concentrations of PC. It is shown that pedopeptins are nonribosomal peptides with a broad-spectrum activity, including against Gram-positive and Gram-negative bacteria and yeasts.


Subject(s)
Caseins/chemistry , Pedobacter/chemistry , Peptides, Cyclic/antagonists & inhibitors , Peptones/metabolism , Molecular Structure , Pedobacter/metabolism , Peptides, Cyclic/biosynthesis , Peptides, Cyclic/chemistry , Peptones/chemistry
6.
Molecules ; 25(17)2020 Aug 23.
Article in English | MEDLINE | ID: mdl-32842542

ABSTRACT

The effect of γ-aminobutyric acid (GABA) on the metabolome of two strains of Lasiodiplodia theobromae isolated from grapevine that hold a different degree of virulence to the host plant (LA-SOL3 (more virulent), LA-SV1 (less virulent)) was investigated. The culture filtrates and crude extracts from the two strains grown in the presence and absence of 10 mM of GABA were tested for phytotoxicity on tomato plant cuttings and leaves, respectively. Considering the opportunistic nature of this fungus for humans, crude extracts were also tested for cytotoxicity on mammalian cell lines. We found that culture filtrates and crude extracts have a decreased toxicity in the presence of GABA. Metabolomic analysis, conducted on both strains at both growth conditions, revealed the production of several compounds, such as indole-3-carboxylic acid (ICA, which is the main compound produced by L. theobromae), 3-indolecarboxyaldehyde, (3R,4S)-botryodiplodin, (R)-mellein. Finally, data demonstrate that GABA both induces a decrease in the amount of ICA, and a diversification of the metabolites produced by L. theobromae.


Subject(s)
Ascomycota/metabolism , Metabolome/drug effects , Vitis/microbiology , gamma-Aminobutyric Acid/pharmacology , Ascomycota/isolation & purification , Species Specificity
7.
Fungal Biol ; 124(6): 571-578, 2020 06.
Article in English | MEDLINE | ID: mdl-32448448

ABSTRACT

Botryosphaeriaceae fungi are phytopathogens and human opportunists. The influence of temperature on the phytotoxicity and cytotoxicity of culture filtrates of five Botryosphaeriaceae species was investigated. All culture filtrates of fungi grown at 25 °C were phytotoxic: symptoms were evaluated based on visual inspection of necrosis areas and on the maximum quantum yield of photosystem II, Fv/Fm. Diplodiacorticola and Neofusicoccum kwambonambiense were the most phytotoxic, followed by Neofusicoccum parvum CAA704 and Botryosphaeria dothidea. Phytotoxicity dramatically decreased when strains were grown at 37 °C, except for B. dothidea. All strains, except N. parvum CAA366 and Neofusicoccum eucalyptorum, grown either at 25 °C or 37 °C, were toxic to mammalian cells; at 25 °C and at 37°C, D. corticola and B. dothidea were the most cytotoxic, respectively. Although the toxicity of B. dothidea to both cell lines and of N. kwambonambiense to Vero cells increased with temperature, the opposite was found for the other species tested. Our results suggest that temperature modulates the expression of toxic compounds that, in a scenario of a global increase of temperature, may contribute to new plant infections but also human infections, especially in the case of B. dothidea.


Subject(s)
Ascomycota/pathogenicity , Cell Survival , Plant Diseases/microbiology , Solanum lycopersicum/microbiology , 3T3 Cells , Animals , Ascomycota/physiology , Chlorocebus aethiops , Mice , Plant Leaves/microbiology , Temperature , Vero Cells
8.
Adv Protein Chem Struct Biol ; 121: 199-235, 2020.
Article in English | MEDLINE | ID: mdl-32312422

ABSTRACT

The interactome - the network of protein-protein interactions (PPIs) within a cell or organism - is technically difficult to assess. Bioinformatic tools can, not only, identify potential PPIs that can be later experimentally validated, but also be used to assign functional meaning to PPIs. Saliva's potential as a non-invasive diagnostic fluid is currently being explored by several research groups. But, in order to fully attain its potential, it is necessary to achieve the full characterization of the mechanisms that take place within this ecosystem. The onset of omics technologies, and specifically of proteomics, delivered a huge set of data that is largely underexplored. Quantitative information relative to proteins within a given context (for example a given disease) can be used by computational algorithms to generate information regarding PPIs. These PPIs can be further analyzed concerning their functional meaning and used to identify potential biomarkers, therapeutic targets, defense and pathogenicity mechanisms. We describe a computational pipeline that can be used to identify and analyze PPIs between human and microbial proteins. The pipeline was tested within the scenario of human PPIs of systemic (Zika Virus infection) and of oral conditions (Periodontal disease) and also in the context of microbial interactions (Candida-Streptococcus) and showed to successfully predict functionally relevant PPIs. The pipeline can be applied to different scientific areas, such as pharmacological research, since a functional meaningful PPI network can provide insights on potential drug targets, and even new uses for existing drugs on the market.


Subject(s)
Bacterial Proteins/metabolism , Dental Caries/microbiology , Fungal Proteins/metabolism , Gingivitis/microbiology , Mouth/microbiology , Periodontitis/microbiology , Salivary Proteins and Peptides/metabolism , Bacterial Proteins/immunology , Biomarkers/metabolism , Dental Caries/genetics , Dental Caries/immunology , Dental Caries/metabolism , Fungal Proteins/immunology , Gingivitis/genetics , Gingivitis/immunology , Gingivitis/metabolism , Host-Pathogen Interactions , Humans , Microbiota/immunology , Mouth/immunology , Mouth/metabolism , Mouth Neoplasms/genetics , Mouth Neoplasms/immunology , Mouth Neoplasms/metabolism , Mouth Neoplasms/microbiology , Peri-Implantitis/genetics , Peri-Implantitis/immunology , Peri-Implantitis/metabolism , Peri-Implantitis/microbiology , Periodontitis/genetics , Periodontitis/immunology , Periodontitis/metabolism , Precancerous Conditions/genetics , Precancerous Conditions/immunology , Precancerous Conditions/metabolism , Precancerous Conditions/microbiology , Protein Interaction Mapping , Proteomics/methods , Salivary Proteins and Peptides/immunology
9.
Toxins (Basel) ; 12(4)2020 04 07.
Article in English | MEDLINE | ID: mdl-32272814

ABSTRACT

Neofusicoccum parvum is a fungal pathogen associated with a wide range of plant hosts. Despite being widely studied, the molecular mechanism of infection of N. parvum is still far from being understood. Analysis of N. parvum genome lead to the identification of six putative genes encoding necrosis and ethylene-inducing proteins (NLPs). The sequence of NLPs genes (NprvNep 1-6) were analyzed and four of the six NLP genes were successfully cloned, expressed in E. coli and purified by affinity chromatography. Pure recombinant proteins were characterized according to their phytotoxic and cytotoxic effects to tomato leaves and to mammalian Vero cells, respectively. These assays revealed that all NprvNeps tested are cytotoxic to Vero cells and also induce cell death in tomato leaves. NprvNep2 was the most toxic to Vero cells, followed by NprvNep1 and 3. NprvNep4 induced weaker, but, nevertheless, still significant toxic effects to Vero cells. A similar trend of toxicity was observed in tomato leaves: the most toxic was NprvNep 2 and the least toxic NprvNep 4. This study describes for the first time an overview of the NLP gene family of N. parvum and provides additional insights into its pathogenicity mechanism.


Subject(s)
Fungal Proteins/toxicity , Plant Leaves/drug effects , Solanum lycopersicum/drug effects , Animals , Ascomycota/genetics , Ascomycota/metabolism , Cell Survival/drug effects , Chlorocebus aethiops , Chlorophyll/metabolism , Cloning, Molecular , Fungal Proteins/genetics , Fungal Proteins/metabolism , Solanum lycopersicum/metabolism , Necrosis , Plant Leaves/metabolism , Recombinant Proteins/toxicity , Vero Cells
10.
J Bras Pneumol ; 45(6): e20180148, 2019.
Article in English, Portuguese | MEDLINE | ID: mdl-31576908

ABSTRACT

OBJECTIVE: To investigate parameters of lung function and respiratory muscle strength in different stages of Parkinson's disease (PD), as well as to determine their correlation with motor function and quality of life. METHODS: This was a cross-sectional study conducted at a referral center for PD in the city of Recife, Brazil. Respiratory muscle strength and lung function, as well as their relationship with motor function and quality of life, were evaluated in patients with PD, stratified by the level of severity, and were compared with the data obtained for a control group. After confirming the normality of data distribution, we performed one-way ANOVA with a post hoc t-test. RESULTS: The sample comprised 66 individuals, in two groups: PD (n = 49) and control (n = 17). All of the parameters investigated showed inverse correlations with PD severity, and there were significant differences among the levels of severity, as well as between the PD and control groups, in terms of the MIP, MEP, FVC, FEV1, and FEF25-75%. The lung function parameters also showed moderate to weak inverse correlations with bradykinesia and rigidity. On a quality of life questionnaire, the total score and mobility domain score both presented a moderate inverse correlation with FVC, FEV1, PEF, and MEP. CONCLUSIONS: Respiratory muscle strength and some lung function parameters are impaired from the early stages of PD onward, bradykinesia and rigidity being the cardinal signs that correlate most strongly with impairment of those parameters. Such alterations negatively affect the quality of life of patients with PD.


Subject(s)
Lung/physiopathology , Muscle Strength/physiology , Parkinson Disease/physiopathology , Quality of Life , Respiratory Muscles/physiopathology , Aged , Analysis of Variance , Body Size/physiology , Case-Control Studies , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Reference Values , Respiratory Function Tests , Statistics, Nonparametric , Surveys and Questionnaires
11.
J. bras. pneumol ; 45(6): e20180148, 2019. tab, graf
Article in English | LILACS | ID: biblio-1040288

ABSTRACT

ABSTRACT Objective: To investigate parameters of lung function and respiratory muscle strength in different stages of Parkinson's disease (PD), as well as to determine their correlation with motor function and quality of life. Methods: This was a cross-sectional study conducted at a referral center for PD in the city of Recife, Brazil. Respiratory muscle strength and lung function, as well as their relationship with motor function and quality of life, were evaluated in patients with PD, stratified by the level of severity, and were compared with the data obtained for a control group. After confirming the normality of data distribution, we performed one-way ANOVA with a post hoc t-test. Results: The sample comprised 66 individuals, in two groups: PD (n = 49) and control (n = 17). All of the parameters investigated showed inverse correlations with PD severity, and there were significant differences among the levels of severity, as well as between the PD and control groups, in terms of the MIP, MEP, FVC, FEV1, and FEF25-75%. The lung function parameters also showed moderate to weak inverse correlations with bradykinesia and rigidity. On a quality of life questionnaire, the total score and mobility domain score both presented a moderate inverse correlation with FVC, FEV1, PEF, and MEP. Conclusions: Respiratory muscle strength and some lung function parameters are impaired from the early stages of PD onward, bradykinesia and rigidity being the cardinal signs that correlate most strongly with impairment of those parameters. Such alterations negatively affect the quality of life of patients with PD.


RESUMO Objetivo: Investigar a repercussão de parâmetros de função pulmonar e de força muscular respiratória nos diversos estágios da doença de Parkinson (DP) e suas correlações com a funcionalidade e a qualidade de vida desses pacientes. Métodos: Estudo de corte transversal realizado em um serviço de referência para DP em Recife (PE). Foram avaliadas a força muscular respiratória e a função pulmonar, assim como suas relações com a funcionalidade e a qualidade de vida, em pacientes com DP estratificados por gravidade da DP e comparados a um grupo controle. Após a verificação da normalidade da amostra, foi realizada one-way ANOVA e teste t post hoc. Resultados: A amostra foi composta por 66 indivíduos, sendo 49 no grupo DP e 17 no grupo controle. Houve reduções nos parâmetros investigados com a progressão da doença, em comparação com o grupo controle, sendo encontradas diferenças significativas em PImáx, PEmáx, CVF, VEF1 e FEF25-75% em todos os estágios da DP. Houve correlações inversas (de fraca a moderada) de alguns parâmetros estudados com bradicinesia e rigidez. Os escores totais do questionário de qualidade de vida e de seu domínio mobilidade apresentaram moderada correlação inversa com CVF, VEF1, PFE e PEmáx. Conclusões: A força muscular respiratória e alguns parâmetros de função pulmonar encontram-se reduzidos desde os estágios iniciais da DP, sendo a bradicinesia e a rigidez os sinais cardinais mais correlacionados ao prejuízo desses parâmetros. Essas alterações repercutem negativamente na qualidade de vida desses pacientes.


Subject(s)
Humans , Male , Female , Middle Aged , Aged , Parkinson Disease/physiopathology , Quality of Life , Respiratory Muscles/physiopathology , Muscle Strength/physiology , Lung/physiopathology , Reference Values , Respiratory Function Tests , Case-Control Studies , Cross-Sectional Studies , Surveys and Questionnaires , Analysis of Variance , Statistics, Nonparametric , Body Size/physiology
12.
New Phytol ; 214(3): 1132-1144, 2017 May.
Article in English | MEDLINE | ID: mdl-28152190

ABSTRACT

Phototrophic organisms need to ensure high photosynthetic performance whilst suppressing reactive oxygen species (ROS)-induced stress occurring under excess light conditions. The xanthophyll cycle (XC), related to the high-energy quenching component (qE) of the nonphotochemical quenching (NPQ) of excitation energy, is considered to be an obligatory component of photoprotective mechanisms. The pigment composition of at least one representative of each major clade of Ulvophyceae (Chlorophyta) was investigated. We searched for a light-dependent conversion of pigments and investigated the NPQ capacity with regard to the contribution of XC and the qE component when grown under different light conditions. A XC was found to be absent in a monophyletic group of Ulvophyceae, the Bryopsidales, when cultivated under low light, but was triggered in one of the 10 investigated bryopsidalean species, Caulerpa cf. taxifolia, when cultivated under high light. Although Bryopsidales accumulate zeaxanthin (Zea) under high-light (HL) conditions, NPQ formation is independent of a XC and not related to qE. qE- and XC-independent NPQ in the Bryopsidales contradicts the common perception regarding its ubiquitous occurrence in Chloroplastida. Zea accumulation in HL-acclimated Bryopsidales most probably represents a remnant of a functional XC. The existence of a monophyletic algal taxon that lacks qE highlights the need for broad biodiversity studies on photoprotective mechanisms.


Subject(s)
Chlorophyta/physiology , Photochemical Processes , Phylogeny , Chlorophyta/growth & development , Chlorophyta/radiation effects , Darkness , Light , Stress, Physiological/radiation effects , Thermodynamics , Xanthophylls/metabolism , Zeaxanthins
13.
Crit Rev Microbiol ; 42(1): 106-26, 2016.
Article in English | MEDLINE | ID: mdl-24754251

ABSTRACT

Bacterial collagenases are metalloproteinases involved in the degradation of the extracellular matrices of animal cells, due to their ability to digest native collagen. These enzymes are important virulence factors in a variety of pathogenic bacteria. Nonetheless, there is a lack of scientific consensus for a proper and well-defined classification of these enzymes and a vast controversy regarding the correct identification of collagenases. Clostridial collagenases were the first ones to be identified and characterized and are the reference enzymes for comparison of newly discovered collagenolytic enzymes. In this review we present the most recent data regarding bacterial collagenases and overview the functional and structural diversity of bacterial collagenases. An overall picture of the molecular diversity and distribution of these proteins in nature will also be given. Particular aspects of the different proteolytic activities will be contextualized within relevant areas of application, mainly biotechnological processes and therapeutic uses. At last, we will present a new classification guide for bacterial collagenases that will allow the correct and straightforward classification of these enzymes.


Subject(s)
Bacteria/enzymology , Collagenases/physiology , Animals , Bacteria/classification , Bacteria/genetics , Cell Culture Techniques , Collagen/chemistry , Collagen/genetics , Collagen/metabolism , Collagenases/chemistry , Collagenases/classification , Collagenases/therapeutic use , Cosmetics , Food Technology , Gelatinases/metabolism , Humans , Matrix Metalloproteinases/metabolism , Proteolysis
14.
Photochem Photobiol Sci ; 14(6): 1169-78, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25959378

ABSTRACT

Oxidative stress induced by photodynamic treatment of microbial cells causes irreversible damages to vital cellular components such as proteins. Photodynamic inactivation (PDI) of bacteria, a promising therapeutic approach for the treatment of superficial and localized skin and oral infections, can be achieved by exciting a photosensitizing agent with visible light in an oxygenated environment. Although some studies have addressed the oxidative alterations of PDI in bacterial proteins, the present study is the first to compare the electrophoretic profiles of proteins of Gram-positive and Gram-negative bacteria, having two structurally different porphyrins, with different kinetics of photoinactivation. The cationic porphyrins 5,10,15-tris(1-methylpyridinium-4-yl)-20-(pentafluorophenyl)porphyrin tri-iodide (Tri-Py(+)-Me-PF) and 5,10,15,20-tetrakis(1-methylpyridinium-4-yl)porphyrin tetra-iodide (Tetra-Py(+)-Me) were used to photosensitize Escherichia coli and Staphylococcus warneri upon white light irradiation at an irradiance of 4.0 mW cm(-2). After different photosensitization periods, proteins were extracted from bacteria and analyzed using one-dimensional SDS-PAGE. Apparent molecular weights and band intensities were determined after an irradiation period corresponding to a reduction of 4 log10 in cell viability. After photodynamic treatment, there was a general loss of bacterial proteins, assigned to large-scale protein degradation. Protein loss was more pronounced after PDI with Tri-Py(+)-Me-PF in both bacteria. There was also an increase in the concentration of some proteins as well as an increase in the molecular weight of other proteins. We show that proteins of E. coli and S. warneri are important targets of PDI. Although there is an attempt of cellular response to the PDI-induced damage by overexpression of a limited number of proteins, the damage is lethal. Our results show that changes occurring in the protein pattern during photodynamic treatment are different with the two photosensitizers, which helps to explain the different inactivation kinetics of the two bacteria. SDS-PAGE is a rational approach to assign the type of cellular response to stress that is being induced in the cells.


Subject(s)
Escherichia coli/drug effects , Gene Expression Regulation, Bacterial/drug effects , Porphyrins/pharmacology , Staphylococcus/drug effects , Cell Survival/drug effects , Electrophoresis, Polyacrylamide Gel , Models, Biological , Molecular Structure , Photochemotherapy , Photosensitizing Agents/pharmacology
15.
Macromol Biosci ; 15(5): 647-56, 2015 May.
Article in English | MEDLINE | ID: mdl-25626858

ABSTRACT

Bacterial phenotypes, such as biofilm formation, antibiotic resistance and virulence expression, are associated with quorum sensing. Quorum sensing is a density-dependent regulatory system of gene expression controlled by specific signal molecules, such as N-acyl homoserine lactones (AHLs), produced and released by bacteria. This study reports the development of linear polymers capable to attenuate quorum sensing by adsorption of AHLs. Linear polymers were synthesized using MMA as backbone monomer and methacrylic acid and itaconic acid as functional monomers. Two different quorum sensing-controlled phenotypes, Vibrio fischeri bioluminescence and Aeromonas hydrophila biofilm formation, were evaluated to test the polymers' efficiency. Results showed that both phenotypes were significantly affected by the polymers, with the itaconic acid-containing material being more effective than the methacrylic acid one. The polymer inhibitory effects were reverted by the addition of lactones, confirming attenuation of quorum sensing through sequestration of signal molecules. The polymers also showed no cytotoxicity when tested using a mammalian cell line.


Subject(s)
Aeromonas hydrophila/drug effects , Polymers/pharmacology , Quorum Sensing/drug effects , Vibrio/drug effects , Acyl-Butyrolactones/chemistry , Aeromonas hydrophila/growth & development , Animals , Biofilms/drug effects , Biofilms/growth & development , Cell Death/drug effects , Chlorocebus aethiops , Chromatography, Gel , Colony Count, Microbial , Luminescence , Magnetic Resonance Spectroscopy , Phenotype , Polymerization , Polymers/chemical synthesis , Polymers/chemistry , Vero Cells , Vibrio/physiology
16.
J Virol Methods ; 209: 103-9, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25241141

ABSTRACT

Reactive oxygen species can be responsible for microbial photodynamic inactivation due to its toxic effects, which include severe damage to proteins, lipids and nucleic acids. In this study, the photo-oxidative modifications of the proteins of a non-enveloped T4-like bacteriophage, induced by the cationic porphyrin 5,10,15-tris(1-methylpyridinium-4-yl)-20-(pentafluorophenyl)porphyrin tri-iodide were evaluated. Two methods were used: sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and infrared spectroscopy. SDS-PAGE analysis showed that the phage protein profile was considerably altered after photodynamic treatment. Seven protein bands putatively corresponding to capsid and tail tube proteins were attenuated and two other were enhanced. Infrared spectroscopy confirmed the time-dependent alteration on the phage protein profile detected by SDS-PAGE, indicative of a response to oxidative damage. Infrared analysis showed to be a promising and rapid screening approach for the analysis of the modifications induced on viral proteins by photosensitization. In fact, one single infrared spectrum can highlight the changes induced to all viral molecular structures, overcoming the delays and complex protocols of the conventional methods, in a much simple and cost effective way.


Subject(s)
Coliphages/chemistry , Coliphages/drug effects , Photosensitizing Agents/metabolism , Porphyrins/metabolism , Viral Proteins/analysis , Coliphages/isolation & purification , Electrophoresis, Polyacrylamide Gel , Protein Binding , Spectrophotometry, Infrared
17.
Rev Bras Reumatol ; 54(2): 110-6, 2014.
Article in English, Portuguese | MEDLINE | ID: mdl-24878857

ABSTRACT

OBJECTIVE: We studied the effect of swimming on the somatic and bone growth of female rats. METHODS: 40 neonate Wistar female rats were separated into: monosodium glutamate group (GluM, n = 20) and received MSG solution (4.0 mg/g) on alternate days during the first 14 days after birth, and Saline group (SAL, n = 20) which received saline solution for the same period of time and at the same dose.At 60 days of age, GluM group was ovariectomized (GluMO) and SAL group just suffered surgical stress. Subsequently, half the animals in each group started swimming, resulting in groups: sedentary saline (SALsed, n = 10), swimming saline (SALswi, n = 10), sedentary ovariectomized Glutamate (GluMOsed, n = 10) and swimming ovariectomized Glutamate (GluMOswi, n = 10). At the end of the experiment, we measured the animals' longitudinal length and weight; their radius was weighed and its length measured. RESULTS: The animals of the GluMOsed group had lower body weight and longitudinal length compared to SALsed. Swimming decreased body weight, but had no influence on the longitudinal length of the GluMOswi group compared to GluMOsed group. Longitudinal length and body weight were lower in SALswi animals compared to SALsed animals. Radius weight and length of GluMOsed animals were lower than in SALsed animals. There was no difference in these parameters between GluMOsed and GluMOswi groups; however, these parameters were lower in SALswi animals compared to SALsed animals. CONCLUSION: Swimming does not influence previously affected bone tissue during the neonatal period, however it may cause damage to healthy bone tissue.


Subject(s)
Bone Resorption/prevention & control , Swimming , Animals , Animals, Newborn , Female , Postmenopause , Rats , Rats, Wistar
18.
Can J Microbiol ; 60(5): 332-42, 2014 May.
Article in English | MEDLINE | ID: mdl-24802941

ABSTRACT

Phytopathogenic fungi are known for producing an arsenal of extracellular enzymes whose involvement in the infection mechanism has been suggested. However, these enzymes are largely unknown and their biotechnological potential also remains poorly understood. In this study, the production and thermostability of extracellular enzymes produced by phytopathogenic Botryosphaeriaceae was investigated. Hydrolytic and oxidative activities were detected and quantified at different temperatures. Most strains (70%; 37/53) were able to produce simultaneously cellulases, laccases, xylanases, pectinases, pectin lyases, amylases, lipases, and proteases. Surprisingly for mesophilic filamentous fungi, several enzymes proved to be thermostable: cellulases from Neofusicoccum mediterraneum CAA 001 and from Dothiorella prunicola CBS 124723, lipases from Diplodia pinea (CAA 015 and CBS 109726), and proteases from Melanops tulasnei CBS 116806 were more active at 70 °C than at any of the other temperatures tested. In addition, lipases produced by Diplodia pinea were found to be significantly more active than any other known lipase from Botryosphaeriales. The thermal activity profile and the wide array of activities secreted by these fungi make them optimal producers of biotechnologically relevant enzymes that may be applied in the food and the health industries (proteases), the pulp-and-paper and biofuel industries (cellulases), or even in the detergent industry (lipases, proteases, amylases, and cellulases).


Subject(s)
Fungi/enzymology , Industrial Microbiology , Cellulases/isolation & purification , Fungi/classification , Hydrolases/isolation & purification , Lipase/isolation & purification , Peptide Hydrolases/isolation & purification
19.
Fungal Biol ; 118(5-6): 516-23, 2014.
Article in English | MEDLINE | ID: mdl-24863480

ABSTRACT

The characterisation of the secretome of phytopathogenic fungi may contribute to elucidate the molecular mechanisms of pathogenesis. This is particularly relevant for Diplodia corticola, a fungal plant pathogen belonging to the family Botryosphaeriaceae, whose genome remains unsequenced. This phytopathogenic fungus is recognised as one of the most important pathogens of cork oak, being related to the decline of cork oak forests in the Iberian Peninsula. Unfortunately, secretome analysis of filamentous fungi is limited by the low protein concentration and by the presence of many interfering substances, such as polysaccharides, which affect the separation and analysis by 1D and 2D gel electrophoresis. We compared six protein extraction protocols concerning their suitability for further application with proteomic workflows. The protocols involving protein precipitation were the most efficient, with emphasis on TCA-acetone protocol, allowing us to identify the most abundant proteins on the secretome of this plant pathogen. Approximately 60% of the spots detected were identified, all corresponding to extracellular proteins. Most proteins identified were carbohydrate degrading enzymes and proteases that may be related to D. corticola pathogenicity. Although the secretome was assessed in a noninfection environment, potential virulence factors such as the putative glucan-ß-glucosidase, neuraminidase, and the putative ferulic acid esterase were identified. The data obtained forms a useful basis for a deeper understanding of the pathogenicity and infection biology of D. corticola. Moreover, it will contribute to the development of proteomics studies on other members of the Botryosphaeriaceae.


Subject(s)
Ascomycota/metabolism , Fungal Proteins/metabolism , Plant Diseases/microbiology , Quercus/microbiology , Virulence Factors/metabolism , Ascomycota/chemistry , Ascomycota/genetics , Ascomycota/isolation & purification , Electrophoresis, Gel, Two-Dimensional , Fungal Proteins/chemistry , Fungal Proteins/genetics , Molecular Sequence Data , Protein Transport , Proteomics , Virulence Factors/chemistry , Virulence Factors/genetics
20.
Rev. bras. reumatol ; 54(2): 110-116, Mar-Apr/2014. tab
Article in Portuguese | LILACS | ID: lil-710224

ABSTRACT

Objetivo: Estudou-se o efeito da natação sobre o crescimento somático e ósseo de ratas. Métodos: usaram-se 40 ratas Wistar neonatas separadas em grupo glutamato monossódico (GluM, n = 20), que recebeu solução de MSG (4 mg/g), em dias alternados, nos primeiros 14 dias de vida; e Grupo Salina (SAL, n = 20), que recebeu solução salina na mesma dose e no mesmo período. Aos 60 dias de vida, o grupo GluM foi ovariectomizado (GluMO) e o SAL passou apenas pelo estresse cirúrgico. Posteriormente, metade dos animais de cada grupo iniciou o treinamento de natação, o que resultou nos grupos Salina sedentário (SALsed, n = 10), Salina natação (SALnat, n = 10), Glutamato ovariectomia sedentário (GluMOsed, n = 10) e Glutamato ovariectomia natação (GluMOnat, n = 10). Ao término do experimento, os animais tiveram o comprimento longitudinal mensurado e foram pesados; o rádio foi pesado e o comprimento, avaliado. Resultados: Os animais do grupo GluMOsed apresentaram peso corpóreo e comprimento longitudinal menores em relação ao SALsed. A natação diminuiu o peso corpóreo, porém não exerceu influência no comprimento longitudinal dos animais do grupo GluMOnat em relação ao GluMOsed. Peso corpóreo e comprimento longitudinal foram menores nos animais do grupo SALnat quando comparados aos do SALsed. Peso e comprimento do rádio dos animais do grupo GluMOsed foram menores do que os do SALsed. Não houve diferença desses parâmetros entre os grupos GluMOsed e GluMOnat. Contudo, foram menores nos animais do grupo SALnat em relação ao SALsed. Conclusão: O treino de natação não exerce influência no tecido ósseo previamente afetado durante o período neonatal e ainda pode causar prejuízo ao tecido ósseo sadio .


Objective: We studied the effect of swimming on the somatic and bone growth of female rats. Methods: 40 neonate Wistar female rats were separated into: monosodium glutamate group (GluM, n = 20) and received MSG solution (4.0 mg/g) on alternate days during the first 14 days after birth, and Saline group (SAL, n = 20) which received saline solution for the same period of time and at the same dose.At 60 days of age, GluM group was ovariectomized (GluMO) and SAL group just suffered surgical stress. Subsequently, half the animals in each group started swimming, resulting in groups: sedentary saline (SALsed, n = 10), swimming saline (SALswi, n = 10), sedentary ovariectomized Glutamate (GluMOsed, n = 10) and swimming ovariectomized Glutamate (GluMOswi, n = 10). At the end of the experiment, we measured the animals' longitudinal length and weight; their radius was weighed and its length measured. Results: The animals of the GluMOsed group had lower body weight and longitudinal length compared to SALsed. Swimming decreased body weight, but had no influence on the longitudinal length of the GluMOswi group compared to GluMOsed group. Longitudinal length and body weight were lower in SALswi animals compared to SALsed animals. Radius weight and length of GluMOsed animals were lower than in SALsed animals. There was no difference in these parameters between GluMOsed and GluMOswi groups; however, these parameters were lower in SALswi animals compared to SALsed animals. Conclusion: Swimming does not influence previously affected bone tissue during the neonatal period, however it may cause damage to healthy bone tissue. .


Subject(s)
Animals , Female , Rats , Bone Resorption/prevention & control , Swimming , Animals, Newborn , Postmenopause , Rats, Wistar
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