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High concentrations of metals in the environment alter bacterial diversity, selecting resistant and tolerant species. The study evaluated the selection of a potential bacterial strain from Sepetiba Bay-Rio de Janeiro, Brazil marine sediments to remove Cu and Pb. The bacterial strain isolated from the sediments was used in three different bioassays: (1) Cu at concentrations of 0 (control), 6 and 50 μg.mL -1 ; (2) Pb at concentrations of 0 (control), 6 and 50 μg.mL -1 ; (3) Cu + Pb in concentrations of 3 μg.mL -1 Cu + 3 μg.mL -1 Pb (6 μg.mL -1 ) and 25 μg.mL -1 Cu + 25 μg.mL -1 Pb (50 μg.mL -1 ). The number of cells and the enzymatic activities of dehydrogenases and esterases were quantified. Results of taxonomic identification indicated the selection of the Pseudomonas stutzeri W228 strain, showing a greater degree of similarity (±73%) with the database used. There was no significant variation in the number of cells, 10 8 cells.mL -1 , which represents a high biomass production in the presence of stressors. However, we observed a reduction in dehydrogenase activity at all tested concentrations of Cu, Pb and Cu + Pb. The activity of esterase increased, indicating a higher energy demand to complete the bacterial life cycle. The study showed significant results for the absorption of Pb by the extracellular polymeric substances (EPS) and the efflux of Cu. The capacity of Pb absorption by EPS can be considered a resistance mechanism, as well as the efflux of Cu, so that the available EPS sites could be occupied by the most toxic ions demonstrating that Pseudomonas stutzeri is resistant to Pb and Cu.

One of the most difficult challenges facing the coal mining industry is rehabilitation of open cut mines in the absence of sufficient quality and quantity of topsoil. As a result, the growth medium for rehabilitation of open cut mines is often mine spoil that has poor chemical and structural properties. Microorganisms play a critical role in natural soil forming processes, nutrient cycling and soil aggregate stabilisation. However, soil microbiota and their impact on soil chemistry and structure has traditionally been overlooked in mine site remediation and mine spoil amelioration. Soil bioengineering, using microbial inoculants to modify soil chemistry and structure, is a novel approach that has the potential to positively alter the chemical and physical limitations prevented by mine spoil and improve mine site rehabilitation outcomes. This review focuses on the importance of microbiology in the spoil-to-soil transformation after open cut coal mining and discusses the ways that microbial inoculants could be used to accelerate the amelioration of coal mine spoil during rehabilitation. The work seeks to establish a platform for soil bioengineering approaches to be considered during rehabilitation of open cut coal mines. The review focuses on Australian open cut coal mines but has application for all mines with nutrient limited substrates and/or saline or sodic spoil that is prone to erosion.

ABSTRACT. The influence of copper on the ciliate Euplotes sp. and associated bacteria isolated from sediment samples of Guanabara Bay were investigated in bioassays. This region is highly affected by heavy metals such as copper, from solid waste constantly dumped in the bay and other sources such as industrial effluents, antifouling paints, atmospheric deposition and urban drainage, and even today there are few data on the metal toxicity to the ecosystem of the Bay of Guanabara. Bioassays were conducted to estimate the LC 50 -24 h of copper, in order to determine the concentration of metal bearing 50% of the population mortality. The results indicated that the concentrations of 0.05 and 0.009 mg L -1 presented no toxicity to Euplotes sp. The associated bacteria are tolerant to copper concentrations used in bioassays, and suggest that they could be used as a potential agent in the bioremediation of areas affected by copper. Keywords: Euplotes sp., bacteria, copper, heavy metals, Guanabara Bay, southeast Brazil.Influencia del cobre sobre Euplotes sp. y la población de bacterias asociada RESUMEN. La influencia del cobre sobre el ciliado Euplotes sp. y las bacterias asociadas aisladas de muestras de sedimentos de la bahía de Guanabara fueron investigados en bioensayos. Esta región está altamente afectada por metales pesados, como el cobre, a partir de residuos sólidos constantemente vertidos en la bahía y de otras fuentes, como los efluentes industriales, pinturas antiincrustantes, deposición atmosférica y drenaje urbano, y hasta hoy hay pocos datos sobre la toxicidad del metal para el ecosistema de la bahía de Guanabara. Se efectuaron bioensayos para estimar la CL 50 -24 h de cobre para determinar la concentración de metales que lleva al 50% de la mortalidad de la población. Los resultados indicaron que las concentraciones de 0,05 y 0,009 mg L -1 , no representan toxicidad para Euplotes sp. Las bacterias asociadas son tolerantes a las concentraciones de cobre utilizadas en los bioensayos, lo que sugiere que podrían ser utilizadas como un agente potencial en la biorremediación de las zonas afectadas por el cobre. Palabras clave: Euplotes sp., bacterias, cobre, metales pesados, bahía de Guanabara, sureste de Brasil.

A deficiência visual é uma limitação no campo da visão, comumente subdividida entre indivíduos cegos ou com baixa visão. Esta situação estabelece a necessidade de modificação dos padrões normalmente estabelecidos para a maioria das pessoas que não apresentam estas características. Neste trabalho procurou-se analisar a demanda de material didático especializado, na área da biologia, solicitada por alunos com deficiência visual, matriculados no ensino médio regular, além de procurar contextualizar todos os fatores acerca das questões que envolvem as pessoas com deficiência visual e a Educação inclusiva. A partir dessa análise foi proposto como objetivo o desenvolvimento do caderno de Genética. Esse material, adaptado, serviu como ferramenta para auxiliar professores e alunos no processo de ensino-aprendizagem de alunos deficientes visuais.