Herbicides are widely used in agricultural practices for preventing the proliferation of weeds. Upon reaching soil and water, herbicides can harm nontarget organisms, such as bacteria, which need an efficient defense mechanism to tolerate stress induced by herbicides. 2,4-Dichlorophenoxyacetic acid (2,4-D) is a herbicide that exerts increased oxidative stress among bacterial communities. Bacterial isolates were obtained from the biofilm of tanks containing washing water from the packaging of different pesticides, including 2,4-D. The Pseudomonas sp. CMA-7.3 was selected because of its tolerance against 2,4-D toxicity, among several sensitive isolates from the biofilm collection. This study aimed to evaluate the antioxidative response system of the selected strain to 2,4-D. It was analyzed the activity of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and guaiacol peroxidase GPX enzymes, that are poorly known in the literature for bacterial systems. The Pseudomonas sp. CMA-7.3 presented an efficient response system in balancing the production of hydrogen peroxide, even at 25x the dose of 2,4-D used in agriculture. The antioxidative system was composed of Fe–SOD enzymes, less common than Mn–SOD in bacteria, and through the activities of KatA and KatB isoforms, working together with APX and GPX, having their activities coordinated possibly by quorum sensing molecules. The peroxide control is poorly documented for bacteria, and this work is unprecedented for Pseudomonas and 2,4-D. Not all bacteria harbor efficient response system to herbicides, therefore they could affect the diversity and functionality of microbiome in contaminated soils, thereby impacting agricultural production, environment sustainability and human health.

Herbicides are widely used in agricultural practices for preventing the proliferation of weeds that compete with crops for survival. Upon reaching soil and water, herbicides can damage nontarget organisms, such as bacteria, which need an efficient defense mechanism to tolerate the stress induced by herbicides. 2,4-Dichlorophenoxyacetic acid (2,4-D) is a herbicide that exerts increased oxidative stress among bacterial communities that consequently witness an increased toxicity in their microenvironments. Bacterial isolates were obtained from the biofilm of water that was contaminated with 2,4-D. This biofilm originated from the tanks containing washing water from the packaging of different pesticides, including 2,4-D. Moreover, several isolates were sensitive to biofilm toxicity; however, they remained alive in the presence of 2,4-D. The Pseudomonas sp. CMA-7.3 was selected because of its tolerance against biofilm agrochemicals. Therefore, the objective of this study is to evaluate the antioxidative response system of the Pseudomonas sp. CMA-7.3. This study also analyzed poorly evaluated enzymes, such as superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and guaiacol peroxidase GPX, in the bacterial systems. The toxic effects of 2,4-D on bacteria were evaluated using mechanisms indicating oxidative stress, such as growth curve, cell viability, peroxide, and malondialdehyde. The Pseudomonas sp. CMA-7.3 was an efficient response system against the activity of antioxidant enzymes such as SOD, CAT, APX, and GPX in balancing the production of H 2 O 2 , even at high doses as 25x the field dose of the herbicide, thereby proving the toxicity of 2,4-D for this strain and showing the ability of the strain to tolerate 2,4-D. The adaptation of this microorganism to herbicide exposure is truly relevant for improving future metabolic studies on bacterial communities. The strain showed a great potential in the application and developmental prospects of a new product in the bioremediation process of environments contaminated by these herbicides.

O presente texto apresenta análise sobre a formação de professores para a educação inclusiva em uma universidade pública do estado do Paraná.  Para tanto utiliza de pesquisa bibliográfica e documental sobre a temática, além de dados coletados em questionário aplicados a graduandos de licenciaturas na referida instituição. A análise dos dados indica que disciplinas voltadas para a educação inclusiva são relevantes para o processo formativo de futuros profissionais e que a presença de disciplinas voltadas para a discussão teórica e prática sobre a atuação docente para o Público Alvo da Educação Inclusiva ainda são insuficientes ou inexistentes na maioria dos cursos de licenciatura, fato que causa insegurança para a futura atuação profissional dos pesquisados.