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The genome assembly of Anopheles darlingi consists of 2221 scaffolds (N50 = 115,072 bp) and has a size spanning 136.94 Mbp. This assembly represents one of the smallest genomes among Anopheles species. Anopheles darlingi genomic DNA fragments of ~37 Kb were cloned, end-sequenced, and used as probes for fluorescence in situ hybridization (FISH) with salivary gland polytene chromosomes. In total, we mapped nine DNA probes to scaffolds and autosomal arms. Comparative analysis of the An. darlingi scaffolds with homologous sequences of the Anopheles albimanus and Anopheles gambiae genomes identified chromosomal rearrangements among these species. Our results confirmed that physical mapping is a useful tool for anchoring genome assemblies to mosquito chromosomes. Published version

Petroleum degrading microorganisms have been isolated from different environments with the purpose of being used in bioremediation processes in areas impacted by petroleum spills. The objective of this study was to evaluate the ability of Bacillus toyonensis AM07 strain to metabolize petroleum compounds. The strain was isolated from the effluent dike of the Urucu Petroleum Province, Coari - Amazonas, Brazil. The degrading activity of B. toyonensis was evaluated by the colorimetric method using the redox indicator 2,6-dichlorophenol indophenol (DCPIP). Thus, the microorganism was inoculated into minimal medium with DCPIP, and with petroleum as the sole carbon source. The degradation potential of the microorganism was found by changing the DCPIP staining and absorbance readings 600nm. The results obtained demonstrated that the bacterial strain was able to degrade petroleum by altering the color of the medium from blue to colorless and by reducing the concentration of the indicator in the absorbance readings. B. toyonensis AM07 strain has shown good performance in the petroleum degradation assays and may be used in the future in remediation technologies for hydrocarbon impacted environments.

A wild-type yeast that could ferment D-xylose was isolated from the abdominal content of Nasutitermes sp. collected in the Central Amazon rainforest using sugarcane bagasse hemicellulosic hydrolyzate (SBHH) as selective medium. The yeast was identified as Meyerozyma guilliermondii. Its ability to ferment D-xylose was assessed using liquid medium containing Durham tubes. A fermentometer assay showed a low ethanol yield using D-xylose as the carbon source. Cell viability after heat shock and ethanol shock was 39.8% and 56.0%, respectively. Cultivation in SBHH (pH = 5.0) showed its capability to perform saccharification of this substrate, increasing total reducing sugar concentration to 42.6%. The log phase was observed between 36 and 108 hours of cultivation with a highest specific growth rate (µMAX) of 0.10 h-1. After 120 hours, 79.5% of total reducing sugar was consumed giving a biomass yield of 0.52 g/g. The final pH of SBHH (7.6) showed that M. guilliermondii was able to neutralize the acids of this substrate. These results agree with some predictions in the early eighties, which stated that investigations about microbial content of termite guts would provide new tools for bioconversion of lignocellulosic biomass to fuels and other added-value chemicals. This work is the first report for this species associated with termites in the Amazonian habitat.

Peach palm is a native Amazonian fruit species with broad genetic diversity in its wild and domesticated populations. This study completed the molecular characterization and genetic analysis of the accessions in the Peach Palm genebank, Brazil, using RAPD markers. Eight primers generated 132 markers, of which 128 were polymorphic. Average heterozigosity was 0.35, with 95.5% polymorphism. The genetic variability within the landraces (H S) was 0.32, while genetic divergence (G ST) was 0.09 among the four well-represented landraces. The average gene flow was 5.0, with high gene flow between the Solimões and Pampa Hermosa (Nm=10.07), and between the Putumayo and Solimões (Nm=10.73) landraces, all western landraces. The dendrograms of the Nei's and Rogers' genetic distances of the well-represented landraces presented similar groupings to previous analyses, with the Solimões, Putumayo and Pampa Hermosa landraces grouped together in western Amazonia, and distant from the Pará landrace in central and eastern Amazonia. A pupunheira é uma fruteira nativa da Amazônia com ampla diversidade genética em suas populações silvestres e domesticadas. Este estudo finalizou a caracterização e análise genética dos acessos do germoplasma, usando marcadores moleculares RAPDs. Oito iniciadores geraram 132 marcadores, com 128 polimórficos. A heterozigosidade média foi 0.35 com 95.5% de polimorfismo, similares a outros estudos. A variabilidade dentro (Hs) das raças bem representadas foi 0,32, enquanto a divergência genética (G ST) foi 0,09 entre as quatro raças bem representadas. O fluxo gênico médio foi 5,0, com alto fluxo gênico entre as raças Solimões e Pampa Hermosa (Nm=10,07), e as raças Putumayo e Solimões (Nm=10,73), sendo todas ocidentais. Os dendrogramas das distâncias de Nei e Rogers mostraram que raças bem representadas apresentaram grupos similares às análises anteriores, com as raças Solimões, Putumayo e Pampa Hermosa agrupadas no oeste da Amazônia, e distantes da raça Pará no centro e leste da Amazônia.

Peach palm is a native Amazonian fruit species with broad genetic diversity in its wild and domesticated populations. This study completed the molecular characterization and genetic analysis of the accessions in the Peach Palm genebank, Brazil, using RAPD markers. Eight primers generated 132 markers, of which 128 were polymorphic. Average heterozigosity was 0.35, with 95.5% polymorphism. The genetic variability within the landraces (H S) was 0.32, while genetic divergence (G ST) was 0.09 among the four well-represented landraces. The average gene flow was 5.0, with high gene flow between the Solimões and Pampa Hermosa (Nm=10.07), and between the Putumayo and Solimões (Nm=10.73) landraces, all western landraces. The dendrograms of the Nei's and Rogers' genetic distances of the well-represented landraces presented similar groupings to previous analyses, with the Solimões, Putumayo and Pampa Hermosa landraces grouped together in western Amazonia, and distant from the Pará landrace in central and eastern Amazonia.

Zeyheria montana, an endemic species of the Bignoniaceae family from the Brazilian Cerrado's known for its anti-cancer properties, is widely used as imuno stimulant in the popular medicine and its therapeutic activity must be validated by scientific data. The objective of this work was to evaluate the genetic variability of eight plant populations collected within the state of São Paulo, Brazil, via Random Amplification of Polymorphic DNA (RAPD) used as molecular markers. After an optimized protocol for the amplification reaction, nine selected primers generated 105 reproducible bands, indicating up to 60% polymorphism. Analysis of molecular variance (AMOVA) revealed higher genetic variation within populations (84.03%) than among populations (15.97%). The variation values estimated by phiST (0.160) indicated moderate to high inter population structuration. Levels of similarity inter plants with genetic and geographical distances, estimated by the unweighted pair-group method analysis (UPGMA) clustering and non-metric multidimensional scaling (NMDS) ordination methods and by the Mantel test (-0.2345 p = 0.118) denoted that the structure found follows the island model, which assumes that a single population of infinite size may have initiated the existing populations of Zeyheria montana, with no spatial position correlation. Based on the obtained data, a germplasm bank from individuals representing the species variability was established. Furthermore the information here reported can be of importance to develop strategies for the conservation of Z. montana. Zeyheria montana, planta arbustiva da família Bignoniaceae, é uma espécie endêmica do Cerrado e possui atividade anti-câncer, sendo utilizada como estimulante na medicina popular. O objetivo deste estudo foi avaliar a variabilidade genética de oito populações localizadas no estado de São Paulo, utilizando marcadores moleculares de Polimorfismo de DNA Amplificado ao Acaso (RAPD). Após a otimização da reação de amplificação, nove iniciadores selecionados geraram 105 fragmentos RAPD reprodutíveis, sendo que a maioria (60,0%) foi polimórfica. A análise molecular de variância (AMOVA) mostrou que a variabilidade dentro de populações (84,03%) foi maior que entre populações (15,97%). As estimativas de variação fiST (0,1597) indicam estruturação populacional moderadamente alta. O agrupamento por meio de UPGMA, a ordenação pelo NMDS e o teste de Mantel entre as matrizes de distâncias genéticas e geográficas demonstraram que a estruturação encontrada segue um modelo de "ilhas", onde uma única população de tamanho infinito pode ter dado origem às populações atuais de Zeyheria, sem relação com sua posição espacial. Com base nos resultados obtidos foi estruturado um banco de germoplasma de indivíduos, representando a variabilidade da espécie. Adicionalmente, as informações deste estudo são importantes para dar suporte a estratégias de conservação de Z. montana.

The restriction endonuclease BliAI, an isoschizomer of ClaI, which recognizes the sequence 5'- AT¯CGAT - 3', was purified from a natural isolate identified as Bacillus licheniformis. The restriction endonuclease was isolated from cell extracts using single-step purification by phosphocellulose column chromatography. The restriction endonuclease is active at 37ºC and over a wide range of pH and salt concentration. The molecular weight of the purified restriction enzyme is consistent with a value of 39 kDa. A endonuclease de restrição BliAI, um isoesquisômero de ClaI, que reconhece a seqüência 5'- AT¯CGAT - 3', foi purificada de um isolado natural identificado como Bacillus licheniformis. A endonuclease de restrição em questão foi isolada a partir de um extrato celular em um único passo cromatográfico utilizando uma coluna contendo a resina fosfocelulose. A endonuclease de restrição é ativa à 37ºC e em uma ampla escala de pH e concentração de sais. O peso molecular da enzima purificada corresponde a um valor de kDa 39.

A strain of Bacillus pumilus was isolated and identified from water samples collected from a small affluent of the Amazon River. Type II restriction endonuclease activity was detected in these bacteria. The enzyme was purified and the molecular weight of the native protein estimated by gel filtration and SDS-PAGE. The optimum pH, temperature and salt requirements were determined. Quality control assays showed the complete absence of "nonspecific nucleases." Restriction cleavage analysis and DNA sequencing of restriction fragments allowed the unequivocal demonstration of 5´GAG¯CTC3´ as the recognition sequence. This enzyme was named BpuAmI and is apparently a neoschizomer of the prototype restriction endonuclease SacI. This is the first report of an isoschizomer and/or neoschizomer of the prototype SacI identified in the genus Bacillus. Uma linhagem de Bacillus pumilus foi isolada e identificada de amostras de águas coletadas em um pequeno Igarapé do Rio Amazonas. Foi detectada atividade de restrição do tipo II nesta bactéria. A enzima foi purificada e o peso molecular da proteína nativa foi estimado por gel filtração e por eletroforese em gel de poliacrilamida. Foram determinados, o pH e temperatura ótimos e as necessidades de sais. Os ensaios do controle de qualidade mostraram uma ausência completa de "nucleases não específicas". As analises das clivagens e o seqüenciamento do DNA dos fragmentos de restrição permitiram uma demonstração inequívoca de que 5´GAG¯CTC 3´ é a seqüência de reconhecimento da enzima. Esta enzima foi denominada de BpuAmI e aparentemente é um neoesquisômero da enzima protótipo SacI. Este é o primeiro relato de um isoesquisômero e/ou neoesquisômero da enzima protótipo SacI identificada no gênero Bacillus.

Das plantas tóxicas da Amazônia Palicourea longiflora e Strychnos cogens foram isolados 571 fungos endofíticos e 74 bactérias endofíticas. Palicourea longiflora (Rubiaceae) e outras espécies desse gênero estão relacionadas a 90% das mortes de gado na região Amazônica. Strychnos cogens (Loganiaceae) e outras espécies de Strychnos são utilizadas pelos indígenas na confecção de "curares". Entre os endófitos isolados de P. longiflora foram identificados os fungos: Colletotrichum sp. e seu telemorfo Glomerella sp., Guignardia sp., Aspergillus niger, Phomopsis sp. e Xylaria sp., além da bactéria Burkholderia gladioli, pertencente a um grupo de fixadoras de nitrogênio. Dos isolados de S. cogens foram identificados os fungos: Colletotrichum sp., Guignardia sp., Aspergillus niger e Trichoderma sp. Uma amostra de 79 isolados fúngicos teve seus metabólitos extracelulares bioensaiados contra microrganismos patogênicos e fitopatogênicos: 19 isolados inibiram um ou mais microrganismos-teste. Dos oito isolados com melhores resultados de inibição, as móleculas bioativas eram menores que 12.000 daltons, fato verificado pela diálise dos metabólitos. Palicourea longiflora (Rubiaceae), a toxic plant from the Amazon belonging to the genus related to 90% of cattle death in the region, and Strychnos cogens (Loganiaceae)belonging to a genus whose plants are used by Indians for manufacturing "curares", were sources of 571 fungi isolates and 74 bacteria isolates. The fungi Colletotrichum sp., Guignardia sp., Aspergillus niger, Glomerella sp., Phomopsis sp. and Xylaria sp. and the endophytic bacterium Burkholderia gladioli were identified from P. longiflora, while the fungi Colletotrichum sp., Guignardia sp., Aspergillus niger and Trichoderma sp. were identified from S. cogens. Bioassays of fungi metabolites excreted by 79 isolates against pathogenic and phytopathogenic microorganisms showed that 19 products inhibited at least one of the microorganisms tested. Through metabolite dialysis it was possible to check the eight best inhibition results, observing that the bioactive molecules were smaller than 12.000 daltons.