Do Archaea and bacteria co-infection have a role in the pathogenesis of chronic chagasic cardiopathy?

Chronic cardiopathy (CC) in Chagas disease is a fibrotic myocarditis with C5b-9 complement deposition. Mycoplasma and Chlamydia may interfere with the complement response. Proteolytic enzymes and archaeal genes that have been described in Trypanosoma cruzi may increase its virulence. Here we tested the hypothesis that different ratios of Mycoplasma, Chlamydia and archaeal organisms, which are frequent symbionts, may be associated with chagasic clinical forms. MATERIALS AND METHODS: eight indeterminate form (IF) and 20 CC chagasic endomyocardial biopsies were submitted to in situ hybridization, electron and immunoelectron microscopy and PCR techniques for detection of Mycoplasma pneumoniae (MP), Chlamydia pneumoniae(CP), C5b-9 and archaeal-like bodies. RESULTS: MP and CP-DNA were always present at lower levels in CC than in IF (p < 0.001) and were correlated with each other only in CC. Electron microscopy revealed Mycoplasma, Chlamydia and two types of archaeal-like bodies. One had electron dense lipid content (EDL) and was mainly present in IF. The other had electron lucent content (ELC) and was mainly present in CC. In this group, ELC correlated negatively with the other microbes and EDL and positively with C5b-9. The CC group was positive for Archaea and T. cruzi DNA. In conclusion, different amounts of Mycoplasma, Chlamydia and archaeal organisms may be implicated in complement activation and may have a role in Chagas disease outcome.FAPESPCNPqFundação Zerbin

Metagenomics in Polluted Aquatic Environments

Metagenomics is defined as the culture-independent genomic analysis of biological assemblages providing access to the whole set of genes and genomes from a sample. It encompasses a variety of techniques that are based on (i) total DNA extraction from samples followed by PCR amplification of specific genes, (ii) library construction or amplification and sequencing of the whole genetic material. These methodologies have successfully been applied in studies of composition, dynamics, and functions of microbial communities in a variety of ecosystems including those subjected to anthropogenic modifications (Gilbert & Dupont, 2011). Culture independent methods allow the analysis of a set of metabolic genes from microbial communities, which can be used to determine how environmental conditions such as pollution can shape community composition and the diversity of genes associated with biogeochemical cycles such as those of carbon, nitrogen, and phosphorus (Singh et al., 2009). This approach is also useful for the discovery of novel environmental microorganisms and genes, with important applications for biotechnology, medicine, and bioremediation (Cardoso et al., 2011). This applicability has resulted in a recent sharp increase in studies focusing in the metagenomic analysis of polluted sites. Their aim is to characterize microbial communities from a diverse set of environments such as freshwater, marine sediments, open ocean, pelagic ecosystems, soil, and host-associated communities. An example of these initiatives is the Global Ocean Sampling Expedition (GOS), which assessed the genetic diversity of marine microbial communities around the Earth. Since 2003, an enormous amount of data has been generated by GOS helping scientists to reveal the microbial diversity and also allowing them to better understand microbial phylogeny and ecology (Gilbert & Dupont, 2011)

Gut Bacterial Communities in the Giant Land Snail Achatina fulica and Their Modification by Sugarcane-Based Diet

The invasive land snail Achatina fulica is one of the most damaging agricultural pests worldwide representing a potentially serious threat to natural ecosystems and human health. This species is known to carry parasites and harbors a dense and metabolically active microbial community; however, little is known about its diversity and composition. Here, we assessed for the first time the complexity of bacterial communities occurring in the digestive tracts of field-collected snails (FC) by using culture-independent molecular analysis. Crop and intestinal bacteria in FC were then compared to those from groups of snails that were reared in the laboratory (RL) on a sugarcane-based diet. Most of the sequences recovered were novel and related to those reported for herbivorous gut. Changes in the relative abundance of Bacteroidetes and Firmicutes were observed when the snails were fed a high-sugar diet, suggesting that the snail gut microbiota can influence the energy balance equation. Furthermore, this study represents a first step in gaining a better understanding of land snail gut microbiota and shows that this is a complex holobiont system containing diverse, abundant and active microbial communities

Environmental Shaping of Sponge Associated Archaeal Communities

Archaea are ubiquitous symbionts of marine sponges but their ecological roles and the influence of environmental factors on these associations are still poorly understood.We compared the diversity and composition of archaea associated with seawater and with the sponges Hymeniacidon heliophila, Paraleucilla magna and Petromica citrina in two distinct environments: Guanabara Bay, a highly impacted estuary in Rio de Janeiro, Brazil, and the nearby Cagarras Archipelago. For this we used metagenomic analyses of 16S rRNA and ammonia monooxygenase (amoA) gene libraries. Hymeniacidon heliophila was more abundant inside the bay, while P. magna was more abundant outside and P. citrina was only recorded at the Cagarras Archipelago. Principal Component Analysis plots (PCA) generated using pairwise unweighted UniFrac distances showed that the archaeal community structure of inner bay seawater and sponges was different from that of coastal Cagarras Archipelago. Rarefaction analyses showed that inner bay archaeaoplankton were more diverse than those from the Cagarras Archipelago. Only members of Crenarchaeota were found in sponge libraries, while in seawater both Crenarchaeota and Euryarchaeota were observed. Although most amoA archaeal genes detected in this study seem to be novel, some clones were affiliated to known ammonia oxidizers such as Nitrosopumilus maritimus and Cenarchaeum symbiosum.The composition and diversity of archaeal communities associated with pollution-tolerant sponge species can change in a range of few kilometers, probably influenced by eutrophication. The presence of archaeal amoA genes in Porifera suggests that Archaea are involved in the nitrogen cycle within the sponge holobiont, possibly increasing its resistance to anthropogenic impacts. The higher diversity of Crenarchaeota in the polluted area suggests that some marine sponges are able to change the composition of their associated archaeal communities, thereby improving their fitness in impacted environments

Methicillin- and vancomycin-resistant Staphylococcus aureus

Submitted by Alexandre Sousa ([email protected]) on 2015-09-29T11:53:48Z No. of bitstreams: 1 1676-2444-jbpml-51-03-0143.pdf: 159978 bytes, checksum: 9d3d327fff4ec6ffd1d88eb024eb4be4 (MD5)Approved for entry into archive by Alexandre Sousa ([email protected]) on 2015-09-29T11:54:47Z (GMT) No. of bitstreams: 1 1676-2444-jbpml-51-03-0143.pdf: 159978 bytes, checksum: 9d3d327fff4ec6ffd1d88eb024eb4be4 (MD5)Approved for entry into archive by Alexandre Sousa ([email protected]) on 2015-09-29T12:11:19Z (GMT) No. of bitstreams: 1 1676-2444-jbpml-51-03-0143.pdf: 159978 bytes, checksum: 9d3d327fff4ec6ffd1d88eb024eb4be4 (MD5)Made available in DSpace on 2015-09-29T12:11:19Z (GMT). No. of bitstreams: 1 1676-2444-jbpml-51-03-0143.pdf: 159978 bytes, checksum: 9d3d327fff4ec6ffd1d88eb024eb4be4 (MD5) Previous issue date: 2015Fundação Oswaldo Cruz. Instituto Nacional de Controle de Qualidade em Saúde. Departamento de Microbiologia. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Nacional de Controle de Qualidade em Saúde. Departamento de Microbiologia. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Nacional de Controle de Qualidade em Saúde. Departamento de Microbiologia. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Nacional de Controle de Qualidade em Saúde. Departamento de Microbiologia. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Nacional de Controle de Qualidade em Saúde. Departamento de Microbiologia. Rio de Janeiro, RJ, Brasil.Introdução: A contaminação cruzada por Staphylococcus aureus entre pacientes, profissionais e materiais de uso médico em unidades de saúde é uma preocupação constante, o que leva pesquisadores a estudar a prevalência desse patógeno em portadores assintomáticos. Objetivos: Investigamos a colonização e o perfil de suscetibilidade aos antimicrobianos de Staphylococcus spp. em superfícies de artigos médicos e em profissionais de duas unidades básicas de saúde no município do Rio de Janeiro. Materiais e métodos: Foram coletadas 79 amostras que resultaram em 49 isolados, submetidos à caracterização fenotípica e molecular por meio da reação em cadeia da polimerase (PCR) dos genes coa, femA e mecA. Resultados: De acordo com os fenótipos apresentados, os isolados foram identificados como S. aureus (n = 35; 71,42%) e Staphylococcus coagulase negativa (CoNS) (n = 14; 28,57%). Destes 14 isolados, 42,85% foram Staphylococcus coagulase negativa resistentes a meticilina (MRCoNS). Dos 35 S. aureus, 31,42% foram resistentes a meticilina (MRSA). Uma cepa foi resistente a vancomicina e identificada como S. aureus resistente a vancomicina (VRSA) após a detecção do gene vanB. Sessenta e oito por cento foram suscetíveis a meticilina (MSSA). Os genes coa, femA e mecA foram amplificados em 75,51%; 71,42% e 30,61% dos isolados, respectivamente. Após amplificação do gene mecA, 20,41% foram classificados como MRSA e 10,20% como MRCoNS. Conclusão: Nossos resultados mostraram frequência maior de MSSA e MRCoNS entre S. aureus e CoNS, respectivamente, colonizando equipamentos e profissionais de saúde. No entanto, a já descrita transferência do cassete cromossômico estafilocócico mec (SSCmec) de MRCoNS para MSSA poderia alterar esses resultados, aumentando a frequência de cepas MRSA.Introduction: Cross-contamination by Staphylococcus aureusamong patients, professionals and medical supplies in health facilities is a constant concern, leading many researchers to study the prevalence of this pathogen in asymptomatic carriers. Objectives: We investigated the colonization and the antimicrobial susceptibility profile of Staphylococcus spp. on surfaces of medical articles and in professionals from two basic health units in the city of Rio de Janeiro. Materials and methods: Seventy-nine samples resulted in 49 isolates which underwent phenotypic and molecular characterization by polymerase chain reaction (PCR) of coa, mecAand femAgenes. Results: According to the phenotypes, the isolates were identified as S. aureus (n= 35, 71.42%) and coagulase-negative Staphylococcus (CoNS) (n= 14, 28.57%). Among these 14 isolates, 42.85% were methicillin-resistant coagulase negative Staphylococcus (MRCoNS). Among the 35 S. aureus, 31.42% were methicillin resistant (MRSA), and 2.8% were vancomycin resistant, characterized as VRSA. Sixty-eight percent were susceptible to methicillin (MSSA). Genes coa, fem Aand mec Awere amplified from 75.51%, 71.42% and 30.61% of the isolates, respectively. After amplification of the mecAgene, 20.41% were characterized as MRSA, and 10.20% as MRCoNS. The vancomycin-resistant strain was characterized as VRSA after detection of the vanBgene. Conclusion:Our results show a higher frequency of MSSA and MRCoNS among S. aureusand CoNS respectively, colonizing devices and health professionals. However, the already described transfer of the staphylococcal cassette chromosome mec (SSCmec) from MRCoNS to MSSA may alter these results, increasing the frequency of MRSA strains

Microbial Community Compositional Shifts in Bleached Colonies of the Brazilian Reef-Building Coral Siderastrea stellata

The association of metazoan, protist, and microbial communities with Scleractinian corals forms the basis of the coral holobiont. Coral bleaching events have been occurring around the world, introducing changes in the delicate balance of the holobiont symbiotic interactions. In this study, Archaea, bacteria, and eukaryotic phototrophic plastids of bleached colonies of the Brazilian coral Siderastrea stellata were analyzed for the first time, using 16S rRNA gene libraries. Prokaryotic communities were slightly more diverse in healthy than in bleached corals. However, the eukaryotic phototrophic plastids community was more diverse in bleached corals. Archaea phylogenetic analyses revealed a high percentage of Crenarchaeota sequences, mainly related to Nitrosopumilus maritimus and Cenarchaeum symbiosum. Dramatic changes in bacterial community composition were observed in this bleaching episode. The dominant bacterial group was Alphaproteobacteria followed by Gammaproteobacteria in bleached and Betaproteobacteria in healthy samples. Plastid operational taxonomic units (OTUs) from both coral samples were mainly related to red algae chloroplasts (Florideophycea), but we also observed some OTUs related to green algae chloroplasts (Chlorophyta). There seems to be a strong relationship between the Bacillariophyta phylum and our bleached coral samples as clones related to members of the diatom genera Amphora and Nitzschia were detected. The present study reveals information from a poorly investigated coral species and improves the knowledge of coral microbial community shifts that could occur during bleaching episodes

Isolation of aerobic cultivable cellulolytic bacteria from different regions of the gastrointestinal tract of giant land snail Achatina fulica

Submitted by Alexandre Sousa ([email protected]) on 2016-03-10T17:24:02Z No. of bitstreams: 1 fmicb-06-00860.pdf: 1456467 bytes, checksum: 8046b0dd63675ecfbdcf95d9a719403a (MD5)Approved for entry into archive by Alexandre Sousa ([email protected]) on 2016-03-10T17:45:42Z (GMT) No. of bitstreams: 1 fmicb-06-00860.pdf: 1456467 bytes, checksum: 8046b0dd63675ecfbdcf95d9a719403a (MD5)Made available in DSpace on 2016-03-10T17:45:42Z (GMT). No. of bitstreams: 1 fmicb-06-00860.pdf: 1456467 bytes, checksum: 8046b0dd63675ecfbdcf95d9a719403a (MD5) Previous issue date: 2015Instituto Nacional de Metrologia, Qualidade e Tecnologia. Rio de Janeiro, RJ, Brasil / Universidade Federal do Rio de Janeiro. Instituto de Biofísica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.Instituto Nacional de Metrologia, Qualidade e Tecnologia. Rio de Janeiro, RJ, Brasil.Instituto Nacional de Metrologia, Qualidade e Tecnologia. Rio de Janeiro, RJ, Brasil.Instituto Nacional de Metrologia, Qualidade e Tecnologia. Rio de Janeiro, RJ, Brasil / Centro Universitário Estadual da Zona Oeste. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Nacional de Controle de Qualidade em Saúde. Departamento de Microbiologia. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Nacional de Controle de Qualidade em Saúde. Departamento de Microbiologia. Rio de Janeiro, RJ, Brasil.Instituto Nacional de Metrologia, Qualidade e Tecnologia. Rio de Janeiro, RJ, Brasil / Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Departamento de Bioquímica e Biologia Molecular. Rio de Janeiro, RJ, Brasil.Instituto Nacional de Metrologia, Qualidade e Tecnologia. Rio de Janeiro, RJ, Brasil / Universidade Federal do Rio de Janeiro. Instituto de Biofísica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.Instituto Nacional de Metrologia, Qualidade e Tecnologia. Rio de Janeiro, RJ, Brasil / Universidade Federal do Rio de Janeiro. Instituto de Biofísica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.The enzymatic hydrolysis of cellulose by cellulases is one of the major limiting steps in the conversion of lignocellulosic biomass to yield bioethanol. To overcome this hindrance, significant efforts are underway to identify novel cellulases. The snail Achatina fulica is a gastropod with high cellulolytic activity, mainly due to the abundance of glycoside hydrolases produced by both the animal and its resident microbiota. In this study, we partially assessed the cellulolytic aerobic bacterial diversity inside the gastrointestinal tract of A. fulica by culture-dependent methods and evaluated the hydrolytic repertoire of the isolates. Forty bacterial isolates were recovered from distinct segments of the snail gut and identified to the genus level by 16S rRNA gene sequence analysis. Additional phenotypic characterization was performed using biochemical tests provided by the Vitek2 identification system. The overall enzymatic repertoire of the isolated strains was investigated by enzymatic plate assays, containing the following substrates: powdered sugarcane bagasse, carboxymethylcellulose (CMC), p-nitrophenyl-beta-D-glucopyranoside (pNPG), p-nitrophenyl-beta-D-cellobioside (pNPC), 4-methylumbelliferyl-beta-D-glucopyranoside (MUG), 4-methylumbelliferyl-beta-D-cellobioside (MUC), and 4-methylumbelliferyl-beta-D-xylopyranoside (MUX). Our results indicate that the snail A. fulica is an attractive source of cultivable bacteria that showed to be valuable resources for the production of different types of biomass-degrading enzymes