Production of thermostable \u3b2-glucosidase and CMCase by Penicillium sp. LMI01 isolated from the Amazon region

Background: Cellulolytic enzymes of microbial origin have great industrial importance because of their wide application in various industrial sectors. Fungi are considered the most efficient producers of these enzymes. Bioprospecting survey to identify fungal sources of biomass-hydrolyzing enzymes from a high-diversity environment is an important approach to discover interesting strains for bioprocess uses. In this study, we evaluated the production of endoglucanase (CMCase) and \u3b2-glucosidase, enzymes from the lignocellulolytic complex, produced by a native fungus. Penicillium sp. LMI01 was isolated from decaying plant material in the Amazon region, and its performance was compared with that of the standard isolate Trichoderma reesei QM9414 under submerged fermentation conditions. Results: The effectiveness of LMI01was similar to that of QM9414 in volumetric enzymeactivity (U/mL); however, the specific enzyme activity (U/mg) of the former was higher, corresponding to 24.170 U/mg of CMCase and 1.345 U/mg of \u3b2-glucosidase. The enzymes produced by LMI01 had the following physicochemical properties: CMCase activity was optimal at pH 4.2 and the \u3b2-glucosidase activity was optimal at pH 6.0. Both CMCase and \u3b2-glucosidase had an optimum temperature at 60\ub0C and were thermostable between 50 and 60\ub0C. The electrophoretic profile of the proteins secreted by LMI01 indicated that this isolate produced at least two enzymes with CMCase activity, with approximate molecular masses of 50 and 35 kDa, and \u3b2-glucosidases with molecular masses between 70 and 100 kDa. Conclusions: The effectiveness and characteristics of these enzymes indicate that LMI01 can be an alternative for the hydrolysis of lignocellulosic materials and should be tested in commercial formulations

Culturable bacteria associated with Anopheles darlingi and their paratransgenesis potential

Background Malaria remains a major public health problem in South America, mostly in the Amazon region. Among newly proposed ways of controlling malaria transmission to humans, paratransgenesis is a promising alternative. Paratransgenesis aims to inhibit the development of parasites within the vector through the action of genetically modified bacteria. The first step towards successful paratransgenesis in the Amazon is the identification of Anopheles darlingi symbiotic bacteria, which are transmitted vertically among mosquitoes, and are not pathogenic to humans. Methods Culturable bacteria associated with An. darlingi and their breeding sites were isolated by conventional microbiological techniques. Isolated strains were transformed with a GFP expressing plasmid, pSPT-1-GFP, and reintroduced in mosquitoes by feeding. Their survival and persistence in the next generation was assessed by the isolation of fluorescent bacteria from eggs, larvae, pupae and adult homogenates. Results A total of 179 bacterial strains were isolated from samples from two locations, Coari and Manaus. The predominant genera identified in this study were Acinetobacter, Enterobacter, Klebsiella, Serratia, Bacillus, Elizabethkingia, Stenotrophomonas and Pantoea. Two isolated strains, Serratia-Adu40 and Pantoea-Ovo3, were successfully transformed with the pSPT-1-GFP plasmid and expressed GFP. The fluorescent bacteria fed to adult females were transferred to their eggs, which persisted in larvae and throughout metamorphosis, and were detected in adult mosquitoes of the next generation. Conclusion Serratia-Adu40 and Pantoea-Ovo3 are promising candidates for paratransgenesis in An. darlingi. Further research is needed to determine if these bacteria are vertically transferred in nature

Temporal abundance of Aedes aegypti in Manaus, Brazil, measured by two trap types for adult mosquitoes

A longitudinal study was conducted in Manaus, Brazil, to monitor changes of adult Aedes aegypti (L.) abundance. The objectives were to compare mosquito collections of two trap types, to characterise temporal changes of the mosquito population, to investigate the influence of meteorological variables on mosquito collections and to analyse the association between mosquito collections and dengue incidence. Mosquito monitoring was performed fortnightly using MosquiTRAPs (MQT) and BG-Sentinel (BGS) traps between December 2008-June 2010. The two traps revealed opposing temporal infestation patterns, with highest mosquito collections of MQTs during the dry season and highest collections of BGS during the rainy seasons. Several meteorological variables were significant predictors of mosquito collections in the BGS. The best predictor was the relative humidity, lagged two weeks (in a positive relationship). For MQT, only the number of rainy days in the previous week was significant (in a negative relationship). The correlation between monthly dengue incidence and mosquito abundance in BGS and MQT was moderately positive and negative, respectively. Catches of BGS traps reflected better the dynamic of dengue incidence. The findings help to understand the effects of meteorological variables on mosquito infestation indices of two different traps for adult dengue vectors in Manaus

Simplified immunoassay for rapid Dengue serotype diagnosis, revealing insensitivity to non-specific binding interference

Proof of concept of an immunoassay, which is easy to implement, for rapid Dengue virus (DENV) serotype diagnosis, in the early infection stage, is reported. The four-layer assay is immobilized onto a thin gold film and relies on a low cost, disposable polymer biochip for optical surface plasmon resonance sensing and detection. The protocol comprises Neutravidin-Biotin mediated monoclonal antibody (MAB) attachment as the functionalized sensing element. Formation of the MAB-DENV complex results in a pronounced thickness change that is optically recorded in real time, employing a microfluidic set-up. Virus presence is confirmed by atomic force microscopy from the same sample. Serum samples were collected from a patient in acute febrile state. Simultaneous serological analysis by means of the reverse transcription polymerase chain reaction, independently, confirmed presence of DENV2 and DENV3. The protocol proved applicable in presence of strong non-specific binding interference that originates from, and is caused by, various blood, serum and other body fluid constituents. False positive indications for both, negative serum and blood control samples were not observed. The achievable limit of detection was estimated to be 2×104 particles/ml. Eventually, the method can be modified towards detection of other viruses by using the same protocol. Keywords: Immuno-assay, Dengue virus detection, Non-specific bindin

Ocorrência de Aelurostrongylus abstrusus (Railliet, 1898) (Nematoda: Metastrongylidae) infectando o Achatina (Lissachatina) fulica Bowdich, 1822 (Mollusca: Gastropoda) na região amazônica

Submitted by Sandra Infurna ([email protected]) on 2017-01-15T20:36:34Z No. of bitstreams: 1 melissa2_cardenas_etal_IOC_2012.pdf: 1079268 bytes, checksum: 6a4741f7d8217840bcc27fefc22023ad (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2017-01-15T20:46:08Z (GMT) No. of bitstreams: 1 melissa2_cardenas_etal_IOC_2012.pdf: 1079268 bytes, checksum: 6a4741f7d8217840bcc27fefc22023ad (MD5)Made available in DSpace on 2017-01-15T20:46:08Z (GMT). No. of bitstreams: 1 melissa2_cardenas_etal_IOC_2012.pdf: 1079268 bytes, checksum: 6a4741f7d8217840bcc27fefc22023ad (MD5) Previous issue date: 2012UNINILTONLINS. Universidade Nilton Lins. Laboratório de Zoologia Aplicada. Manaus, AM, Brasil.Prefeitura Municipal de Manaus. SEDEMA-Secretaria Municipal de Meio Ambiente. Manaus, AM, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Helmintos Parasitos de Peixes. Rio de Janeiro, RJ, Brasil.UNINILTONLINS. Universidade Nilton Lins. Laboratório de Entomologia Aplicada. Manaus, AM, Brasil.IBAMA. Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis. Escritório Regional de Gurupi. Gurupi, TO, Brasil.UNINILTONLINS. Universidade Nilton Lins. Laboratório de Zoologia Aplicada. Manaus, AM, Brasil.INPA. Instituto Nacional de Pesquisas da Amazônia. Coordenação de Biologia de Água Doce e Pesca. Interior. Manaus, AM, Brasil.Achatina fulica ou “caramujo africano” é uma espécie exótica, considerada uma das cem piores espécies invasoras do mundo, causando sérios danos ambientais. No presente estudo foi registrado, pela primeira vez, a ocorrência do Aelurostrongylus abstrusus infectando o A. fulica na região amazônica. Esse nematóide é descrito parasitando principalmente o sistema pulmonar de felinos, causando a “aelurostrongilose”, também conhecida como estrongiloidose cardio-pulmonar felina. Novos dados morfométricos de larvas de terceiro estágio são apresentados. Dos 45 caramujos coletados, 40% estavam infectados por larvas de A. abstrusus. Especimens de Achatina fulica foram coletados em três áreas da cidade de Manaus: rural, leste e oeste. A zona leste apresentou a maior prevalência de 80%. O grande número de A. fulica encontrado em áreas habitadas aumenta as chances de ocorrência de zoonoses emergentes e destaca a necessidade de mais estudos para o melhor controle da doença.Achatina fulica or “giant African snail” is an exotic species, considered to be one of the world’s hundred most invasive species, causing serious environmental damages. In the present study we report, for the first time, the occurrence of Aelurostrongylus abstrusus infecting A. fulica in the Amazon region. This nematode is described parasitizing mainly the pulmonary system of felines, which causes “aelurostrongilose”, also known as feline cardio-pulmonary strongyloidosis. New morphometric data of third stage larvae are presented herein. The present study demonstrated that 40% of all the snails were infected by A. abstrusus. Achatina fulica specimens were collected from three different areas in Manaus namely: rural; east and west areas. The east area presents the highest prevalence of 80%. The large number of A. fulica found in inhabited areas increases the chances of emergent zoonoses, which highlights the need of further studies so as to better control this disease