RESUMO
Leifsonia xyli subsp. xyli (Lxx) colonizes the xylem vessels of sugarcane, a plant niche where microorganisms are highly exposed to oxidative and osmotic stresses. This study performed an in silico analysis of the genome of Lxx and characterized 16 genes related to the detoxification of oxidative species (peroxidases, O2- dismutases, and methionine reductases) and to the production and transport of osmolytes and analyzed their expression in vitro after 30, 60, and 120 min of exposure to H2O2 or PEG. The PAGE activity of superoxide dismutase (Mn-SOD as confirmed by inhibition tests) and of catalase (CAT) and the accumulation of trehalose were also assessed. Exposure to H2O2 increased the expression of most oxidative-responsive genes and decreased the expression of those related to osmotic responses, whereas the opposite occurred after exposure to PEG. The isoform profiles of CAT and Mn-SOD shifted in response to H2O2 but not to PEG and Lxx cells accumulated more trehalose over time after exposure to PEG compared with non-exposed cells. The experimental results validated the in silico analysis and indicated that this obligate endophytic parasite has multiple and functional mechanisms to combat the stresses imposed by its host.
Assuntos
Actinobacteria/genética , Pressão Osmótica , Estresse Oxidativo/genética , Saccharum/microbiologia , Actinobacteria/patogenicidade , Actinobacteria/fisiologia , Catalase/metabolismo , Interações entre Hospedeiro e Microrganismos , Peroxidação de Lipídeos , Doenças das Plantas/microbiologia , Superóxido Dismutase/metabolismoRESUMO
BACKGROUND: Actinomycetoma is a syndrome of the skin characterized by chronic inflammation and lesions with nodular grain-like structures. The most common aetiological agents are Nocardia brasiliensis and Actinomadura madurae. In response to infection with these organisms the body produces an inflammatory immune response in the skin. The aim of the present study was to determine the production of chemokines, pro-inflammatory cytokines, antimicrobial peptides and the expression of Toll-like receptors (TLRs) in keratinocytes infected by A. madurae. METHODS: A cell line of HaCaT keratinocytes was infected with A. madurae at a multiplicity of infection of 20:1 for 2 h and the samples were collected from 2 to 72 h post-infection. Intracellular replication of the bacterium was evaluated by counting of colony-forming units, the TLR expression and antimicrobial peptide production were assayed by confocal microscopy and chemokine and pro-inflammatory cytokine levels were determined by enzyme-linked immunosorbent assay. RESULTS: Early in the infection, A. madurae was able to achieve intracellular replication in keratinocytes, however, the cells eventually controlled the infection. In response to the infection, keratinocytes overexpressed TLR2 and TLR6, produced high concentrations of cytokines monocyte chemoattractant protein-1, interleukin 8, human ß-defensin-1, human ß-defensin-2 and LL37 and low levels of tumour necrosis factor α. CONCLUSIONS: The human keratinocytes contribute to the inflammatory process in response to A. madurae infection by overexpressing TLRs and producing chemokines, pro-inflammatory cytokines and antimicrobial peptides.
Assuntos
Actinobacteria/patogenicidade , Inflamação/etiologia , Queratinócitos/imunologia , Actinobacteria/isolamento & purificação , Actinomadura , Citocinas/imunologia , Citocinas/isolamento & purificação , Ensaio de Imunoadsorção Enzimática , Humanos , Micetoma/etiologia , Micetoma/fisiopatologia , Dermatopatias Bacterianas/imunologiaRESUMO
The aim of this study was to explore the diversity of culturable bacterial communities residing in blackberry plants (Rubus fruticosus). Bacterial endophytes were isolated from plant roots, and their 16S rDNA sequences were amplified and sequenced. Our results show that the roots of R. fruticosus exhibit low colony forming units of bacterial endophytes per gram of fresh tissue (6 x 102 ± 0.5 x 102). We identified 41 endophytic bacterial species in R. fruticosus by BLAST homology search and a subsequent phylogenetic analysis, belonging to the classes Actinobacteria, Bacilli, Alfaproteobacteria, Betaproteobacteria, and Gammaproteobacteria. Predominantly, genera belonging the Proteobacteria (Burkholderia, 29.4%; Herbaspirillum, 10.7%; Pseudomonas, 4.9%; and Dyella, 3.9%), Firmicutes (Bacillus, 42.1%), and Actinobacteria (two isolates showing high identity with the Streptomyces genus, 1.9%) divisions were identified. Fifty percent of the bacterial endophytes produced the phytohormone indole-acetic acid (IAA), eleven of which exhibited higher IAA production (>5.8 mg/mL) compared to the plant growth-promoting strain, Pseudomonas fluorescens UM270. Additionally, the endophytic isolates exhibited protease activity (22%), produced siderophores (26.4%), and demonstrated antagonistic action (>50% inhibition of mycelial growth) against the grey mold phytopathogen Botrytis cinerea (3.9%). These results suggested that field-grown R. fruticosus plants contain bacterial endophytes within their tissues with the potential to promote plant growth and display antagonism towards plant pathogens.
Assuntos
Filogenia , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética , Rubus/microbiologia , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Actinobacteria/patogenicidade , Betaproteobacteria/genética , Betaproteobacteria/isolamento & purificação , Betaproteobacteria/patogenicidade , Gammaproteobacteria/genética , Gammaproteobacteria/isolamento & purificação , Gammaproteobacteria/patogenicidade , Raízes de Plantas/genética , Pseudomonas fluorescens/genética , Pseudomonas fluorescens/isolamento & purificação , Pseudomonas fluorescens/patogenicidade , Rubus/genéticaRESUMO
The aim of the present study was to evaluate the presence of the periodontal pathogens that form the red complex (Tannerella forsythia, Porphyromonas gingivalis and Treponema denticola) and Aggregatibacter actinomycetemcomitans in patients with chronic periodontitis. The sample consisted of 29 patients with a clinical and radiographic diagnosis of chronic periodontitis based on the criteria of the American Academy of Periodontology (3). Samples for microbiological analysis were collected from the four sites of greatest probing depth in each patient, totaling 116 samples. These samples were processed using conventional polymerase chain reaction, which achieved the following positive results: 46.6% for P. gingivalis, 41.4% for T. forsythia, 33.6% for T. denticola and 27.6% for A. actinomycetemcomitans. P. gingivalis and T. forsythia were more prevalent (p < 0.05) in periodontal pockets ≥ 8 mm. The combinations T. forsythia + P. gingivalis (23.2%) and T. forsythia + P. gingivalis + T. denticola (20.0%) were more frequent in sites with a probing depth ≥ 8 mm. Associations with the simultaneous presence of A. actinomycetemcomitans + P. gingivalis, A. actinomycetemcomitans + T. forsythia, P. gingivalis + T. forsythia and T. forsythia + T. denticola were statistically significant (p < 0.05). It was concluded that the red complex pathogens are related to chronic periodontitis, presenting a higher occurrence in deep periodontal pockets. Moreover, the simultaneous presence of these bacteria in deep sites suggests a symbiotic relationship between these virulent species, favoring, in this way, a further progression of periodontal disease.
Assuntos
Humanos , Actinobacteria/isolamento & purificação , Actinobacteria/patogenicidade , Infecções Bacterianas , Técnicas In Vitro , Periodontite , Porphyromonas gingivalis/isolamento & purificação , Porphyromonas gingivalis/patogenicidade , Reação em Cadeia da Polimerase/métodos , Treponema denticola/patogenicidade , Métodos , Pacientes , VirulênciaRESUMO
As infecções por Corynebacterium pseudotuberculosis são caracterizadas por processos piogranulomatosos crônicos em várias espécies de animais de produção. Nos equinos,bovinos e pequenos ruminantes a infecção por este actinomiceto causa abscesso peitoral ou peito de pombo, linfangite ulcerativa e linfadenite caseosa, respectivamente. O presente estudo procura revisar os principais aspectos da infecção por C. pseudotuberculosis em ruminantes domésticos e equinos, com ênfase nos fatores de virulência, epidemiologia, manifestações clínicas, métodos de diagnósticos, controle, profilaxia e reflexos na saúde pública.(AU)
Corynebacterium pseudotuberculosis infections are characterized by chronic pyogranulotous process in several domestic animals. In equine, bovine and small ruminants the affection by this actinomycete lead to pectoral abscesses, ulcerative limphangites and caseous lymphadenitis, respectively. The present study reviewed the most-important aspects of C. psedotuberculosis infectons, in domestic ruminants and equines, with emphasis for virulence factors of microorganism, epidemiology, clinical manifestations, methods of diagnosis, control aspects and impact in public health of bacteria.(AU)
El Schistosomus reflexus (SR) es una anomalía congénita fatal y rara, que se encuentra principalmente en rumiantes, gestando un feto con plegado de la columna vertebral, la exposición de las vísceras abdominales y torácicas, anquilosis de las extremidades, hipoplasia hepática y diafragmática, escoliosis y anomalías del sistemas digestivo y genitourinario. Fue llevado al Hospital Veterinario, FMVZ - UNESP - Botucatu /SP, una aberración congénita deforme removida por tracción forzada en la distocia de vaca mestiza perteneciente a un ganadero en la ciudad de Lençóis Paulista /SP. Por las características generales y resultados de la necropsia fue posible concluir que este es un caso raro de SR, no hay informes sobre casos similares de esta malformación totalmente cubiertos por la epidermis y dermis. (AU)
Assuntos
Animais , Corynebacterium pseudotuberculosis/patogenicidade , Indústria Agropecuária/classificação , Actinobacteria/patogenicidade , Infecções , Abscesso/complicações , Linfangite/complicaçõesRESUMO
As infecções por Corynebacterium pseudotuberculosis são caracterizadas por processos piogranulomatosos crônicos em várias espécies de animais de produção. Nos equinos,bovinos e pequenos ruminantes a infecção por este actinomiceto causa abscesso peitoral ou peito de pombo, linfangite ulcerativa e linfadenite caseosa, respectivamente. O presente estudo procura revisar os principais aspectos da infecção por C. pseudotuberculosis em ruminantes domésticos e equinos, com ênfase nos fatores de virulência, epidemiologia, manifestações clínicas, métodos de diagnósticos, controle, profilaxia e reflexos na saúde pública.
Corynebacterium pseudotuberculosis infections are characterized by chronic pyogranulotous process in several domestic animals. In equine, bovine and small ruminants the affection by this actinomycete lead to pectoral abscesses, ulcerative limphangites and caseous lymphadenitis, respectively. The present study reviewed the most-important aspects of C. psedotuberculosis infectons, in domestic ruminants and equines, with emphasis for virulence factors of microorganism, epidemiology, clinical manifestations, methods of diagnosis, control aspects and impact in public health of bacteria.
El Schistosomus reflexus (SR) es una anomalía congénita fatal y rara, que se encuentra principalmente en rumiantes, gestando un feto con plegado de la columna vertebral, la exposición de las vísceras abdominales y torácicas, anquilosis de las extremidades, hipoplasia hepática y diafragmática, escoliosis y anomalías del sistemas digestivo y genitourinario. Fue llevado al Hospital Veterinario, FMVZ - UNESP - Botucatu /SP, una aberración congénita deforme removida por tracción forzada en la distocia de vaca mestiza perteneciente a un ganadero en la ciudad de Lençóis Paulista /SP. Por las características generales y resultados de la necropsia fue posible concluir que este es un caso raro de SR, no hay informes sobre casos similares de esta malformación totalmente cubiertos por la epidermis y dermis.