Diagnóstico molecular da infecção por hemoplasmas em gatos domésticos naturalmente infectados da cidade de Belém, Pará

Mycoplasma haemofelis, 'Candidatus Mycoplasma haemominutum' e 'Candidatus Mycoplasma turicensis' são os agentes causadores da micoplasmose felina, que podem causar anemia aguda ou crônica. O objetivo deste trabalho foi determinar a ocorrência de hemoplasmas em gatos domésticos de Belém, Pará. Para isso, 201 gatos foram divididos em três grupos: Grupo A foi composto por 101 gatos de rua capturados pelo Centro de Controle de Zoonoses, o grupo B foi composto por 62 gatos domiciliados e saudáveis e o grupo C foi composto por 38 gatos domiciliados que apresentavam alguma afecção clínica. Foram coletadas amostras de sangue para a realização de Reação em Cadeia pela Polimerase (PCR) para detectar o DNA destes agentes, os quais foram sequenciados e alinhados. A análise estatística foi realizada para detectar a associação entre a infecção, o sexo dos animais e os grupos experimentais. O DNA de pelo menos uma das espécies de hemoplasmas pesquisados foi detectado em 19,9% (40/201) das amostras, sendo o DNA de 'Candidatus M. haemominutum' encontrado em 7,96% (16/201) das amostras, M. haemofelis em 1,49% (3/201) das amostras, enquanto que o DNA de 'Candidatus M. turicensis' foi detectado em 12,93% (26/201) das amostras. O DNA destes três agentes foi detectado em gatos dos grupos A e C, enquanto que no grupo B foi detectado apenas 'Candidatus M. turicensis' e 'Candidatus M. haemominutum' Foi detectada a influência do sexo sobre a infecção hemoplasmas apenas entre 'Candidatus M. haemominutum' e machos. Estes resultados mostraram que os hemoplasmas circulam entre os gatos domésticos em Belém e 'Candidatus M. turicensis' e 'Candidatus M. haemominutum' foram mais comuns do que M. haemofelis, especialmente em gatos vadios.

Mutational meltdown in primary endosymbionts: selection limits Muller's ratchet

Background Primary bacterial endosymbionts of insects (p-endosymbionts) are thought to be undergoing the process of Muller's ratchet where they accrue slightly deleterious mutations due to genetic drift in small populations with negligible recombination rates. If this process were to go unchecked over time, theory predicts mutational meltdown and eventual extinction. Although genome degradation is common among p-endosymbionts, we do not observe widespread p-endosymbiont extinction, suggesting that Muller's ratchet may be slowed or even stopped over time. For example, selection may act to slow the effects of Muller's ratchet by removing slightly deleterious mutations before they go to fixation thereby causing a decrease in nucleotide substitutions rates in older p-endosymbiont lineages. Methodology/Principal Findings To determine whether selection is slowing the effects of Muller's ratchet, we determined the age of the Candidatus Riesia/sucking louse assemblage and analyzed the nucleotide substitution rates of several p-endosymbiont lineages that differ in the length of time that they have been associated with their insect hosts. We find that Riesia is the youngest p-endosymbiont known to date, and has been associated with its louse hosts for only 13–25 My. Further, it is the fastest evolving p-endosymbiont with substitution rates of 19–34% per 50 My. When comparing Riesia to other insect p-endosymbionts, we find that nucleotide substitution rates decrease dramatically as the age of endosymbiosis increases. Conclusions/Significance A decrease in nucleotide substitution rates over time suggests that selection may be limiting the effects of Muller's ratchet by removing individuals with the highest mutational loads and decreasing the rate at which new mutations become fixed. This countering effect of selection could slow the overall rate of endosymbiont extinction.

Genome sequences of the human body louse and its primary endosymbiont provide insights into the permanent parasitic lifestyle

As an obligatory parasite of humans, the body louse (Pediculus humanus humanus) is an important vector for human diseases, including epidemic typhus, relapsing fever, and trench fever. Here, we present genome sequences of the body louse and its primary bacterial endosymbiont Candidatus Riesia pediculicola. The body louse has the smallest known insect genome, spanning 108 Mb. Despite its status as an obligate parasite, it retains a remarkably complete basal insect repertoire of 10,773 protein-coding genes and 57 microRNAs. Representing hemimetabolous insects, the genome of the body louse thus provides a reference for studies of holometabolous insects. Compared with other insect genomes, the body louse genome contains significantly fewer genes associated with environmental sensing and response, including odorant and gustatory receptors and detoxifying enzymes. The unique architecture of the 18 minicircular mitochondrial chromosomes of the body louse may be linked to the loss of the gene encoding the mitochondrial single-stranded DNA binding protein. The genome of the obligatory louse endosymbiont Candidatus Riesia pediculicola encodes less than 600 genes on a short, linear chromosome and a circular plasmid. The plasmid harbors a unique arrangement of genes required for the synthesis of pantothenate, an essential vitamin deficient in the louse diet. The human body louse, its primary endosymbiont, and the bacterial pathogens that it vectors all possess genomes reduced in size compared with their free-living close relatives. Thus, the body louse genome project offers unique information and tools to use in advancing understanding of coevolution among vectors, symbionts, and pathogens.

Detection and identification of species-specific bacteria associated with synanthropic mites

Internal bacterial communities of synanthropic mites Acarus siro, Dermatophagoides farinae, Lepidoglyphus destructor, and Tyrophagus putrescentiae (Acari: Astigmata) were analyzed by culturing and culture-independent approaches from specimens obtained from laboratory colonies. Homogenates of surface-sterilized mites were used for cultivation on non-selective agar and DNA extraction. Isolated bacteria were identified by sequencing of the 16S rRNA gene. PCR amplified 16S rRNA genes were analyzed by terminal restriction fragment length polymorphism analysis (T-RFLP) and cloning sequencing. Fluorescence in situ hybridization using universal bacterial probes was used for direct bacterial localization. T-RFLP analysis of 16S rRNA gene revealed distinct species-specific bacterial communities. The results were further confirmed by cloning and sequencing (284 clones). L. destructor and D. farinae showed more diverse communities then A. siro and T. putrescentiae. In the cultivated part of the community, the mean CFUs from four mite species ranged from 5.2 × 102 to 1.4 × 103 per mite. D. farinae had significantly higher CFUs than the other species. Bacteria were located in the digestive and reproductive tract, parenchymatical tissue, and in bacteriocytes. Among the clones, Bartonella-like bacteria occurring in A. siro and T. putresecentiae represented a distinct group related to Bartonellaceae and to Bartonella-like symbionts of ants. The clones of high similarity to Xenorhabdus cabanillasii were found in L. destructor and D. farinae, and one clone related to Photorhabdus temperata in A. siro. Members of Sphingobacteriales cloned from D. farinae and A. siro clustered with the sequences of “Candidatus Cardinium hertigii” and as a separate novel cluster.

Cardinium endosymbionts are widespread in synanthropic mite species(Acari: Astigmata)

‘Candidatus Cardinium’ is an intracellular endosymbiont or parasite frequently occurring in invertebrates including mites and ticks. In this work we report Cardinium bacteria in Astigmata mites and explore their incidence in synanthropic species. Amplification of a 776 bp bacterial 16S rRNA gene fragment, using specific primers, enabled identification of closely related Cardinium sequences in 13 laboratory-reared populations of mites. In addition, Cardinium sequences were identified in three wild mite populations. Large scale screening of these populations showed 100% prevalence of Cardinium, representing the highest incidence compared to other major Chelicerate groups.

Estudo fitossanitário, multiplicação e taxonomia de nematoides encontrados em sementes de gramíneas forrageiras no Brasil

Pathogens in seeds imply quarantine constraints for exportation. This research aimed to quantify nematodes and fungus populations in seed samples of forage grasses from the main Brazilian producing states, and to multiply the nematodes in vitro, as well to study the taxonomy of the nematodes detected. Seed samples of 237 lots of different forage grasses from São Paulo, Minas Gerais, Mato Grosso do Sul, Mato Grosso, Bahia, and Goias States were collected and shipped for analyses in the Nematology and Plant Pathology Laboratories at FCAV[long dash]UNESP [long dash] Jaboticabal( SP) by Comercio e Industria Matsuda Imp., Exp. Ltd. Nematodes were extracted from 10 g of seeds. To detect the fungus, the Blotter-test was applied. The identifications were done by using a photonic microscope and a stereomicroscope. For the study of in vitro multiplication of the nematodes, the following parthenogenetic species were selected: Aphelenchoides sexlineatus, Aphelenchus sp. and Ditylenchus montanus. Cultures of the fungi Fusarium sp. and Didymella brioniae were used as substrate to multiply the nematodes in Petri dishes. Each plate was inoculated with 10 mature females, then incubated in B.O.D. at 25 [plus or minus]1 [degree]C, in the dark. Thirty days after inoculation, the nematodes were extracted. The populations obtained in the suspensions were estimated in the microscope using Peters counting chamber, and the reproduction factor estimated. For the taxonomic study of the nematodes, morphological characters of specimens were recorded under the light and scanning electron microscopes. The results indicated a large distribution of nematodes and fungus in seeds of forage grasses in Brazil. The nematodes identified in the present study were: Aphelenchoides besseyi, A. bicaudatus, A. fragariae, A. sexlineatus, Ditylenchus myceliophagus, D. dipsaci, D. montanus, and Aphelenchus sp. In addition, species of the fungi Fusarium, Helminthosporium and Phoma were recovered.

Detection of hemoplasma and Bartonella species and co-infection with retroviruses in cats subjected to a spaying/neutering program in Jaboticabal, SP, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Molecular detection of hemoplasma infection among cats from São Luís island, Maranhão, Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Prevalence and Molecular Characterization of Mycoplasma ovis in Selected Free-Ranging Brazilian Deer Populations

Mycoplasma ovis is a hemoplasma that may cause anemia and mortality in small ruminants. Our aim was to determine whether M. ovis infects populations of free-ranging deer in Brazil. Bully coat samples from 64 Blastocerus dichotomus from Porto Primavera, 18 Ozotocerus bezoarticus from Pantanal, and 21 O. bezoarticus from Emas National Park were tested. Using a M. ovis PCR protocol to amplify extracted DNA, 46/64 (72%) of deer froth Porto Primavera, 10/18 (56%) from Pantanal, and 4/21 (19%) from Emas National Park were positive, giving an overall positive rate of 58% for hemoplasma in these wild deer. Sequencing and phylogenetic analysis of the 168 rRNA gene revealed 3 genetically distinct hemoplasmas including M. ovis, 'Candidatus Mycoplasma erythrocervae', and a hemoplasma most closely related to M. ovis. Phylogenetic analysis of the 23S rRNA gene from selected sequences confirmed these relationships.

Diagnóstico de hemoparasitas em felídeos neotropicais provenientes de vida livre no Brasil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Flutuação populacional e distribuição espacial de Diaphorina citri Kuwayama (Hemiptera: Liviidae) em propriedades citrícolas com manejo intensivo do Huanglongbing

Pós-graduação em Agronomia (Entomologia Agrícola) - FCAV

Isolamento e identificação de bactérias solubilizadoras de fósforo e produtoras de auxinas em solo com cana-de-açúcar

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Detecção sorológica e caracterização moleculares de agentes anaplasmataceae, micoplasmas hemotróficos, piroplasmas e Hepatozoon sp. em carnívoros selvagens mantidos em cativeiro no Brasil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Diagnóstico molecular de hemoparasitas e frequência de anticorpos anti-Toxoplasma gondii e anti-Neospora caninum, em gatos peridomiciliados na cidade de São Luís, Maranhão

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estatística espacial e redes neurais aplicadas no estudo de epidemias de huanglongbing e mancha preta na cultura dos citros

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)