33 research outputs found
Feeding habits of Enyalius perditus (Squamata: Leiosauridae) in an Atlantic Forest remnant in southeastern Brazil
Hábitos alimentares de Enyalius perditus (Squamata: Leiosauridae) em um fragmento de Mata Atlântica no sudeste do Brasil. O objetivo do presente estudo foi fornecer informações sobre hábitos alimentares e outros aspectos ecológicos do lagarto Enyalius perditus em um fragmento de Mata Atlântica no estado do Rio de Janeiro, sudeste do Brasil. No Rio de Janeiro, os indivÃduos de E. perditus alimentaram-se predominantemente de artrópodes, como lagartas, isópodes e aranhas, como é tÃpico de lagartos desse gênero. Não houve variação pronunciada nos principais tipos de presas consumidas entre essa e outras populações de E. perditus estudadas, apesar de haver diferenças potenciais nos suprimentos alimentares entre ambientes. Os indivÃduos consumiram fragmentos de folhas mortas, ingeriram presas comumente encontradas na serapilheira (e.g., Isopoda e larvas de Coleoptera) e foram algumas vezes encontrados no chão ou capturados em armadilhas-de-queda durante os trabalhos de campo, o que sugere que esses lagartos utilizam a serapilheira do chão da floresta para o forrageio e outras atividades, embora também utilizem poleiros acima do nÃvel do chão.Feeding habits of Enyalius perditus (Squamata: Leiosauridae) in an Atlantic Forest remnant in southeastern Brazil. In the present study, we aimed to provide information regarding feeding habits and other ecological aspects of Enyalius perditus in an Atlantic Forest remnant in the state of Rio de Janeiro, southeastern Brazil. Enyalius perditus individuals in Rio de Janeiro fed predominantly upon arthropods such as caterpillars, isopods, and spiders, as is typical of lizards in the genus. There were no pronounced variations in the main types of prey consumed between this and other populations of E. perditus studied in spite of potential differences in local food supplies between environments. The individuals consumed fragments of dead leaves, ingested prey commonly found in leaf litter (e.g., Isopoda and Coleoptera larvae), and were sometime
The Echinococcus canadensis (G7) genome: A key knowledge of parasitic platyhelminth human diseases
Background: The parasite Echinococcus canadensis (G7) (phylum Platyhelminthes, class Cestoda) is one of the causative agents of echinococcosis. Echinococcosis is a worldwide chronic zoonosis affecting humans as well as domestic and wild mammals, which has been reported as a prioritized neglected disease by the World Health Organisation. No genomic data, comparative genomic analyses or efficient therapeutic and diagnostic tools are available for this severe disease. The information presented in this study will help to understand the peculiar biological characters and to design species-specific control tools. Results: We sequenced, assembled and annotated the 115-Mb genome of E. canadensis (G7). Comparative genomic analyses using whole genome data of three Echinococcus species not only confirmed the status of E. canadensis (G7) as a separate species but also demonstrated a high nucleotide sequences divergence in relation to E. granulosus (G1). The E. canadensis (G7) genome contains 11,449 genes with a core set of 881 orthologs shared among five cestode species. Comparative genomics revealed that there are more single nucleotide polymorphisms (SNPs) between E. canadensis (G7) and E. granulosus (G1) than between E. canadensis (G7) and E. multilocularis. This result was unexpected since E. canadensis (G7) and E. granulosus (G1) were considered to belong to the species complex E. granulosus sensu lato. We described SNPs in known drug targets and metabolism genes in the E. canadensis (G7) genome. Regarding gene regulation, we analysed three particular features: CpG island distribution along the three Echinococcus genomes, DNA methylation system and small RNA pathway. The results suggest the occurrence of yet unknown gene regulation mechanisms in Echinococcus. Conclusions: This is the first work that addresses Echinococcus comparative genomics. The resources presented here will promote the study of mechanisms of parasite development as well as new tools for drug discovery. The availability of a high-quality genome assembly is critical for fully exploring the biology of a pathogenic organism. The E. canadensis (G7) genome presented in this study provides a unique opportunity to address the genetic diversity among the genus Echinococcus and its particular developmental features. At present, there is no unequivocal taxonomic classification of Echinococcus species; however, the genome-wide SNPs analysis performed here revealed the phylogenetic distance among these three Echinococcus species. Additional cestode genomes need to be sequenced to be able to resolve their phylogeny.Fil: Maldonado, Lucas Luciano. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en MicrobiologÃa y ParasitologÃa Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologÃa y ParasitologÃa Médica; ArgentinaFil: Assis, Juliana. Fundación Oswaldo Cruz; BrasilFil: Gomes Araújo, Flávio M.. Fundación Oswaldo Cruz; BrasilFil: Salim, Anna C. M.. Fundación Oswaldo Cruz; BrasilFil: Macchiaroli, Natalia. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en MicrobiologÃa y ParasitologÃa Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologÃa y ParasitologÃa Médica; ArgentinaFil: Cucher, Marcela Alejandra. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en MicrobiologÃa y ParasitologÃa Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologÃa y ParasitologÃa Médica; ArgentinaFil: Camicia, Federico. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en MicrobiologÃa y ParasitologÃa Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologÃa y ParasitologÃa Médica; ArgentinaFil: Fox, Adolfo. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en MicrobiologÃa y ParasitologÃa Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologÃa y ParasitologÃa Médica; ArgentinaFil: Rosenzvit, Mara Cecilia. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en MicrobiologÃa y ParasitologÃa Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologÃa y ParasitologÃa Médica; ArgentinaFil: Oliveira, Guilherme. Instituto Tecnológico Vale; Brasil. Fundación Oswaldo Cruz; BrasilFil: Kamenetzky, Laura. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en MicrobiologÃa y ParasitologÃa Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologÃa y ParasitologÃa Médica; Argentin
Evidence for Reductive Genome Evolution and Lateral Acquisition of Virulence Functions in Two Corynebacterium pseudotuberculosis Strains
Ruiz JC, D'Afonseca V, Silva A, et al. Evidence for Reductive Genome Evolution and Lateral Acquisition of Virulence Functions in Two Corynebacterium pseudotuberculosis Strains. PLoS ONE. 2011;6(4): e18551.Background: Corynebacterium pseudotuberculosis, a Gram-positive, facultative intracellular pathogen, is the etiologic agent of the disease known as caseous lymphadenitis (CL). CL mainly affects small ruminants, such as goats and sheep; it also causes infections in humans, though rarely. This species is distributed worldwide, but it has the most serious economic impact in Oceania, Africa and South America. Although C. pseudotuberculosis causes major health and productivity problems for livestock, little is known about the molecular basis of its pathogenicity. Methodology and Findings: We characterized two C. pseudotuberculosis genomes (Cp1002, isolated from goats; and CpC231, isolated from sheep). Analysis of the predicted genomes showed high similarity in genomic architecture, gene content and genetic order. When C. pseudotuberculosis was compared with other Corynebacterium species, it became evident that this pathogenic species has lost numerous genes, resulting in one of the smallest genomes in the genus. Other differences that could be part of the adaptation to pathogenicity include a lower GC content, of about 52%, and a reduced gene repertoire. The C. pseudotuberculosis genome also includes seven putative pathogenicity islands, which contain several classical virulence factors, including genes for fimbrial subunits, adhesion factors, iron uptake and secreted toxins. Additionally, all of the virulence factors in the islands have characteristics that indicate horizontal transfer. Conclusions: These particular genome characteristics of C. pseudotuberculosis, as well as its acquired virulence factors in pathogenicity islands, provide evidence of its lifestyle and of the pathogenicity pathways used by this pathogen in the infection process. All genomes cited in this study are available in the NCBI Genbank database (http://www.ncbi.nlm.nih.gov/genbank/) under accession numbers CP001809 and CP001829
Parameters from the community of leaf-litter frogs from Estação Ecológica Estadual ParaÃso, Guapimirim, Rio de Janeiro State, southeastern Brazil
Herpetofauna of an Atlantic rainforest area (Morro São João) in Rio de Janeiro State, Brazil
Amphibians of an open cerrado fragment in southeastern Brazil
The Cerrado encompasses ca. 2 million km² in Brazil. Most Cerrado areas have been greatly disturbed in the past decades. Only 20% of this biome remain undisturbed, and only 1.2% is protected. Knowledge on the biology and diversity of Cerrado amphibian assemblages is still incipient. Here we present natural history information (habitat use and reproductive activity) of 28 species of frogs from the Estação Ecológica de Itirapina (EEI), and compare the composition of this assemblage with those of other Cerrado areas, other open areas, and a few forest areas throughout Brazil. We demonstrate that the Itirapina assemblage is more similar to those of other open areas than to those of forests, even when the latter are geographically closer. Six species occurred in the gallery forest at varying levels of dependence (three independent, two semi-dependent, and one totally dependent) while all other species occurred exclusively in open areas. For most species at EEI, reproduction was strongly synchronized with the onset of the rainy season, with the exception of Hypsiboas lundii, which called throughout the year, and Proceratophrys sp. which started calling prior to the beginning of the rainy season. The spatial and temporal patterns observed in this assemblage seem to reflect both ecological (e. g. hydroperiod of water bodies) and historical factors (e. g. early breeding in leptodactylids, late breeding in hylids, both phylogenetically constrained)
Amphibians of an open cerrado fragment in southeastern Brazil
The Cerrado encompasses ca. 2 million km² in Brazil. Most Cerrado areas have been greatly disturbed in the past decades. Only 20% of this biome remain undisturbed, and only 1.2% is protected. Knowledge on the biology and diversity of Cerrado amphibian assemblages is still incipient. Here we present natural history information (habitat use and reproductive activity) of 28 species of frogs from the Estação Ecológica de Itirapina (EEI), and compare the composition of this assemblage with those of other Cerrado areas, other open areas, and a few forest areas throughout Brazil. We demonstrate that the Itirapina assemblage is more similar to those of other open areas than to those of forests, even when the latter are geographically closer. Six species occurred in the gallery forest at varying levels of dependence (three independent, two semi-dependent, and one totally dependent) while all other species occurred exclusively in open areas. For most species at EEI, reproduction was strongly synchronized with the onset of the rainy season, with the exception of Hypsiboas lundii, which called throughout the year, and Proceratophrys sp. which started calling prior to the beginning of the rainy season. The spatial and temporal patterns observed in this assemblage seem to reflect both ecological (e. g. hydroperiod of water bodies) and historical factors (e. g. early breeding in leptodactylids, late breeding in hylids, both phylogenetically constrained).O Cerrado originalmente ocupava dois milhões km² no Brasil. Nas últimas décadas, as áreas naturais de Cerrado vêm sendo destruÃdas rapidamente. Somente 20% da região original permanece inalterada e apenas 1,2% encontram-se em unidades de conservação. O conhecimento sobre a biologia e a diversidade de espécies de Cerrado ainda são muito escassos. Neste trabalho, nós apresentamos informações sobre história natural (uso do ambiente e atividade reprodutiva) de 28 espécies de anfÃbios da Estação Ecológica de Itirapina (EEI) e comparamos a composição das taxocenoses da EEI com aquelas de outras localidades de Cerrado, e também de áreas florestais e outras fisionomias abertas. Demonstramos que a taxocenose de Itirapina assemelha-se mais à quelas de outras formações vegetais abertas, estruturalmente mais semelhantes, do que as taxocenoses de formações florestais, mesmo que estas sejam geograficamente mais próximas. Seis espécies ocorreram nas matas de galeria em diferentes graus de dependência (três independentes, duas semi-dependentes e uma totalmente dependente) enquanto que as demais ocorreram exclusivamente nas fisionomias abertas. Para a maioria das espécies da EEI, a reprodução foi fortemente sincronizada com a estação chuvosa, com exceção de H. lundii, que vocalizou durante todo o ano e Proceratophrys sp. que iniciou as atividades de vocalização antes do inÃcio da estação chuvosa. Os padrões espacial e temporal observados nessa taxocenose parecem refletir tanto fatores ecológicos (e. g. hidroperÃodo dos corpos d'água) e históricos (e. g. reprodução no inÃcio da estação reprodutiva para os leptodactilÃdeos e tardia para os hilÃdeos, ambos filogeneticamente determinados).9310