Bactéria açoriana ativa contra mosquitos vetores de infeções

A secção Biologia é coordenada pelo Professor Universitário Armindo Rodrigues.As infeções emergentes ou reemergentes são infeções causadas pela entrada de um agente infeccioso num local considerado indemne até então ou pelo reaparecimento desse agente depois de um longo período de ausência. A globalização, ao aumentar significativamente o movimento de pessoas e o intercâmbio de materiais entre continentes, associada às alterações climáticas, tem contribuído para a disseminação de agentes infeciosos, originando-se assim o aparecimento de novas infeções ou o seu reaparecimento em locais onde terão existido antes. Muitos destes agentes infecciosos têm como hospedeiros intermediários artrópodes que funcionam como vetores para a sua transmissão e também disseminação. Exemplos de vetores são os mosquitos que transmitem um grande número de agentes infecciosos humanos e animais, alguns deles altamente patogénicos, como o protozoário causador da malária, a infeção mais letal no mundo, e muitos vírus, entre eles o causador da Dengue. […].info:eu-repo/semantics/publishedVersio

Life cycle of Popillia japonica Newman (Coleoptera - Scarabaeidae) in Terceira island - Azores.

Na presente nota, descreve-se o ciclo de vida de Popillia japonica Newman, na Ilha Terceira. A emergência inicia-se na última semana de Maio. A população atinge o pico no início de Agosto e decresce até meados de Outubro. O 1.º estado larvar é curto. O 2.º é muito variável, 1 a 5 meses, enquanto que o 3.º estado é o mais longo, entre 6 a 8 meses. O estado de pupa não vai além de 1 mês. São ainda referidos a alimentação dos diversos estados do escaravelho japonês e a mortalidade verificada durante o inverno, em áreas acima dos 300m. Anota-se ainda a presença de algumas larvas parasitadas por Metarhizium anisopliae (Metch.) Sorokin.ABSTRACT: In this paper the life cycle of Popillia japonica Newman in Terceira Island is described. The first adults appear in the last week of May, reach its peak in early August and disappear in middle October. The 1st instar larvae don't last long. The 2nd instar has a life span between 1 and 5 months. The 3rd instar is the one that lasts longer, about 6 to 8 months. The pupae stage is short, less than 1 month. Notes are given on the food habits of adults and larvae. In what concerns the natural enemies, only some larvae were found momified with the green muscardine fungus

Population dynamics of the japanese beetle (Coleoptera - Scarabaeidae) in Terceira Island - Azores.

O escaravelho japonês, Popillia japonica Newman, foi introduzido na Ilha Terceira, no início da década de 70. Desde então, a população tem vindo a aumentar e a dispersar-se pela área de pastagem. As capturas de adultos em 1983 e 1984 mostram que a população aumentou 2,1 vezes, de um ano para o outro. A estimativa da população larvar aponta para um crescimento de cerca de 6 vezes, de 1984 para 1985.ABSTRACT: Since its introduction in Terceira Island in the early 70's, the Japanese beetle (Popillia japonica Newman) has been spreading out from its initial focus of infestation, to the interior agricultural areas of the island, through more favourable zones to its establishment. The data found in the survey trapping, in 1983 and 1984, show an increasing population throughout the area occupied by the pest (2.1 fold). On the other hand, the estimation of the larvae population, in February of 1984 and 1985, allows the prediction of an increase of about 6 times fold in the adult population for the year of 1985

The political and economic dependence of the press in Macao under Portuguese and Chinese rule: continuity and change

The article analyses the media system in Macao, a special administrative region of China that transitioned from Portuguese to Chinese sovereignty in 1999, becoming one of cities in the world with the largest number of published newspapers per capita. Combining historical research with the analysis of contemporary empirical data collected through interviews with journalists working on the ground, the research demonstrates how there is a long tradition of state control that goes back to the colonial era and that has assumed different forms, ranging from outright censorship to physical intimidation of journalists and economic dependence on the government. Limitations and control strategies imposed on news reporting during the Portuguese administration continue to be practiced today by the Chinese authorities. Even so, journalists operating on the Macao media market tend to overstate the level of freedom they are given, which can be attributed to media outlets being economically dependent on the state. Nevertheless, the level of freedom attributed to the press is today higher than it had been during the colonial period with some critical voices being allowed to reach the media. This needs to be understood in the context of what has been defined as the Chinese safety valve strategy.info:eu-repo/semantics/publishedVersio

Interactions between Penicillium brevicompactum/Penicillium expansum and Acinetobacter calcoaceticus isolated from drinking water in biofilm development and control

Available online 13 October 2022Bacteria and filamentous fungi (ff) are commonly encountered in biofilms developed in drinking water (DW) distribution systems (DWDS). Despite their intimate ecological relationships, researchers tend to study bacteria and ff separately. This work assesses the impact of bacteria-ff association in biofilm formation and tolerance to chlorination. One strain of Acinetobacter calcoaceticus isolated from DW was used as a model bacterium. Penicillium brevicompactum and P. expansum isolated from DW were the ff selected. Single species and inter-kingdom adhesion and biofilm formation occurred under two shear stress () conditions (0.05 and 1.6 Pa). The sessile structures were further characterized in terms of biomass production, respiratory activity and structure. The results showed that 1.6 Pa of shear stress and A. calcoaceticus-ff association favoured biofilm production. Inter-kingdom biofilms produced more biomass than A. calcoaceticus single species and reduced A. calcoaceticus susceptibility to disinfection, particularly to high sodium hypochlorite (SHC) concentrations. In addition, P. brevicompactum formed single species biofilms highly resistant to removal and inactivation by SHC. The presence of P. brevicompactum or P. expansum in inter-kingdom biofilms significantly decreased SHC removal and inactivation effects in comparison to the bacterial biofilms alone, proposing that using bacteria to form biofilms representative of DWDS can provide inaccurate conclusions, particularly in terms of biofilm production and susceptibility to disinfection.This work was financially supported by LA/P/0045/2020 (ALiCE), UIDB/00511/2020 and UIDP/00511/2020 (LEPABE) - funded by national funds through the FCT/MCTES (PIDDAC); Projects Germirrad - POCI-01-0247-FEDER-072237; PRESAGE - Aquatic/0007/2020, funded by FEDER funds through COMPETE2020 – Programa Operacional Competitividade e Internacionalizaçao ˜ (POCI) and by national funds (PIDDAC) through FCT/MCTES; Project “HealthyWaters – Identification, Elimination, Social Awareness and Education of Water Chemical and Biological Micropollutants with Health and Environmental Implications”, with reference NORTE-01-0145-FEDER-000069, supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). This study was further supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and by LABBELS – Associate Laboratory in Biotechnology, Bioengineering and Microelectromechnaical Systems, LA/P/0029/2020.info:eu-repo/semantics/publishedVersio

The effects of sodium hypochlorite on the control of inter-kingdom biofilm formation by drinking water-isolated microorganisms

Biofilms in drinking water distribution systems (DWDS) are responsible for several undesirable effects in water. One of the main drawbacks is their potential to protect pathogens from stress conditions. Microbial interactions in biofilms can benefit the survival of co existing microorganisms, including the increased resistance to antimicrobials. Chlorine disinfection is the main widespread strategy used in DWDS for microbial control. Even if new and alternative strategies are being developed, it is conceivable that the future strategies still persist with chlorine due to economic and safety aspects. Therefore, the understanding on the efficacy of chlorine against biofilms is of utmost importance in order to improve the current strategies. The purpose of this work was to assess the effects of sodium hypochlorite (SHC) on the control of single and dual species biofilm formation by selected filamentous fungi (Penicillium expansum and Penicillium brevicompactum) and bacterium (Acinetobacter calcoaceticus) isolated from DWDS. Biofilms were developed during 48 h in 96 wells microtiter plates under two hydrodynamic conditions (25 and 150 rpm). The effects of SHC at several concentrations (0.1, 0.5, 1, 10 and 100 mg/L) was tested. The biofilm control was evaluated using crystal violet (removal) and resazurin (inactivation) dyes. The results shown that, P.brevicompactum biofilms were extremely resistant to disinfection when compared with single species biofilms of P.expansum and dual species biofilms of P.brevicompactum A.calcoaceticus. The association of A.calcoaceticus with both fungi seems beneficial, since the dual species biofilms were more resistant to disinfection. The inactivation and removal occurred for high SHC concentrations. However, total biofilm control was not achieved

Centro de recursos biológicos : novas exigências e oportunidades para a bioeconomia

Desde 1982 que as colecções de culturas microbianas trabalham em conjunto para implementarem uma política comum, partilharem tecnologias e procurarem projectos colaborativos. Adicionalmente, o Grupo de Trabalho em Biotecnologia da Organização para a Cooperação e o Desenvolvimento Económico (OCDE) tem defendido os centros de recursos biológicos (CRBs) como elementos chave na infra-estrutura científica e tecnológica das ciências da vida e biotecnologia. A OCDE, em 2001, publicou um relatório que enfatiza o potencial dos CRBs onde recomenda a criação de uma rede global de CRBs. Na segunda fase desta iniciativa, a OCDE encarregou um grupo de missão com a tarefa de desenvolver um plano de implementação das recomendações enunciadas no relatório. Isto incluiu, (i) normas de funcionamento comum, (ii) normas para ligação e trocas de informação, (iii) acções apropriadas para a segurança, (iv) regulação sobre a gestão da arquitectura institucional e (v) financiamento. Após este trabalho terminado, em 2009 lançou-se o projecto demonstrativo da rede global de CRBs (GBRCN, www.gbrcn.org). Este projeto conta com 15 países e trabalha para aumentar a eficiência das colecções microbianas com vista a garantir padrões de qualidade adequados para que as colecções possam trabalhar em rede. Adicionalmente, a Comissão Europeia apostou no financiamento do projecto europeu do consórcio de centros de recursos microbianos (EMbaRC, www.embarc.eu) como forma de fortalecer a Europa para a bioeconomia e a competitividade. Nesta sequência de esforços e exigências globais e europeias o fornecimento de material biológico de qualidade e com garantia de autenticidade passou a ser, concomitantemente, uma exigência central para as colecções. Em resposta a este contexto, a Micoteca da Universidade do Minho (MUM, www.micoteca.deb.uminho.pt) tem vindo a desenvolver critérios internos de gestão e a aplicar novas tecnologias de identificação, como é o caso do MALDI-TOF ICMS (matrixassisted laser desorptionionisation time-of-flight intact cell mass spectrometry), para garantir uma crescente qualidade e autenticidade dos recursos biológicos que preserva e fornece

Inter-kingdom biofilm formation between bacteria and filamentous fungi isolated from a drinking water distribution system

Background The main challenge to the drinking water (DW) industry is to deliver a product that is microbiologically and chemically safe, aesthetically pleasing and adequate in quantity and delivery pressure. Biofilms constitute one of the major microbial problems in DW distribution systems (DWDS) that most contribute to the deterioration of water quality. Knowledge on DW biofilms has been mainly obtained from studies on bacterial biofilms even though, under natural conditions, they are usually viewed as complex communities where different organisms are present, including filamentous fungi (ff). Studies regarding ff biofilms are scarce despite their ability to form complex and multicellular biofilms [1, 2]. Diversity in microbial communities leads to a variety of complex relationships involving interspecies and intraspecies interactions that need to be understood. The aim of this study was to assess the dynamics of inter-kingdom biofilm formation between commonly detected ff and bacteria in DWDS. Methods The ff Penicillium expansum and the bacteria Acinetobacter calcoaceticus and Methylobacterium oryzae [3] were used as model species. Biofilm formation was performed using microtiter plates with rotatory movements mimicking water flow behaviour in DWDS. Biofilms were analysed at different times in terms of biomass using crystal violet staining, metabolic activity was determined by the resazurin reduction assay and, morphology by epifluorescence, using calcofluor white M2R and DAPI, and bright field microscopies. Results & Conclusion The results confirmed that each individual species forms biofilms at 24, 48 and 72h with increasing biomass over time. Metabolic activity was higher at the 24h biofilms and then decreased overtime. Regarding mixed species biofilms, metabolic activity was higher when compared to single species biofilms at 24h and similar for the 48 and 72h biofilms. The results provided by microscopies allowed the understanding of the distribution of specific organisms in inter-kingdom biofilms.Afonso T.B. and Simões L.C. acknowledge the grants provided by the Portuguese Foundation for Science and Technology (FCT) under grants with the references PD/BD/128033/2016 and SFRH/BPD/81982/2011 respectively.info:eu-repo/semantics/publishedVersio

Pesquisa de bio-insecticidas. Valorização do potencial biológico dos Açores

A secção Biologia é coordenada pelo Professor Universitário Armindo Rodrigues.Uma colecção de bactérias e nemátodes entomopatogénicos isolados nos Açores está a ser uma fonte de bioinsecticidas com actividade e selectividade incrementadas

Stability based on a polyphasic approach of fungal samples preserved on alginate

Alginate-encapsulation is a commonly used, simple and cost effective method to preserve plant samples. Since alginate has been proven to protect tissues against physical and environmental damage, minimising dehydration, it is considered a good preservation technique. The application of this method for the preservation of filamentous fungi was intended to present an alternative to the commonly used preservation methods, especially for recalcitrant fungi. MALDI-TOF MS emerged in the late 1980s as a sound technique to investigate the mass spectrometry of molecular high-mass of organic compounds through a soft ionisation of molecules resulting in minimum fragmentation. This technique has high potential for the identification of filamentous fungi species and occasionally strains. One of the most interesting advantages of the technique is the analysis of intact fungal cells thereby generating peptides and proteins profiles. A novel technique was applied to the preservation of Botrytis cinerea (MUM 10.163, 10.165, 10.167), Aspergillus ibericus (MUM 04.68) and Aspergillus brasiliensis (MUM 06.181) using alginate encapsulation, under two conditions: distilled water (I) and 10% glycerol (II), both at 4°C for 1 year after which the viabilities were studied. A comparison with Castellani preservation in water (III) was made, using viability test, colonial morphology and MALDI-TOF MS analysis for the evaluation of the preservation methods. The strains preserved by condition (I) presented lower viability than those preserved by condition (II). In addition, when comparing the results from the samples preserved by (III) with the ones encapsulated and maintained in 10% glycerol (II), we noted that the latter presented a higher viability, faster growth and health colony formation. The MALDI-TOF MS analysis indicated that the strains clustered according to species. For B. cinerea only small spectral differences (< 5%) were presented in the percentages of similarity, which is in the tolerance range of the technique, except for MUM 10.167 (>5%) when as (III). In the present study we can conclude that the success of the preser