Structuring biofilm communities living in pesticide contaminated water

Abstract

The wide use of pesticides in agriculture expose microbiota to stressful conditions that require the development of survival strategies. The bacterial response to many pollutants has not been elucidated in detail, as well as the evolutionary processes that occur to build adapted communities. The purpose of this study was to evaluate the bacterial population structure and adaptation strategies in planktonic and biofilm communities in limited environments, as tanks containing water used for washing herbicide containers. This biodiversity, with high percentage of nonculturable microorganisms, was characterized based on habitat and abiotic parameters using molecular and bioinformatics tools. According to water and wastewater standards, the physicochemical conditions of the tank water were inadequate for survival of the identified bacteria, which had to develop survival strategies in this hostile environment. The biodiversity decreased in the transition from planktonic to biofilm samples, indicating a possible association between genetic drift and selection of individuals that survive under stressful conditions, such as heating in water and the presence of chlorine, fluorine and agrochemicals over a sixmonth period. The abundance of Enterobacter, Acinetobacter and Pseudomonas in biofilms from water tanks was linked to essential processes, deduced from the genes attributed to these taxonomic units, and related to biofilm formation, structure and membrane transport, quorum sensing and xenobiotic degradation. These characteristics were randomly combined and fixed in the biofilm community. Thus, communities of biofilm bacteria obtained under these environmental conditions serve as interesting models for studying herbicide biodegradation kinetics and the prospects of consortia suitable for use in bioremediation in reservoirs containing herbicide-contaminated wastewater, as biofilters containing biofilm communities capable of degrading herbicides.

Immunological and antioxidant role of curcumin in ameliorating fipronil toxicity in Nile tilapia ( Oreochromis niloticus )

“…Aquatic environments are the final receptors for many xenobiotics including fipronil (FIP). Along the path between the application and the aquatic environment, physico‐chemical and biological changes can occur in a compound, and furthermore, its fate can be governed by these biological degradation and chemical decomposition (Lima et al, 2020).…”

Herbicides Tolerance in a Pseudomonas Strain Is Associated With Metabolic Plasticity of Antioxidative Enzymes Regardless of Selection

“…The tolerance evaluation of bacteria obtained in tanks containing washing water from pesticide containers ( Lima et al, 2020 ) showed that 67.2% of the isolates were sensitive to herbicides Boral ® and Heat ® at 15x and 45x concentrations. It is known that herbicides can be toxic for non-target organisms because of the electronegative characteristics of their active molecules ( Pileggi et al, 2020 ) and can reduce microbial diversity, such as that of Actinobacter in the presence of Granstar, a sulfonylurea herbicide, and that prior exposure to the herbicide acts as a selective agent ( Rachedi et al, 2018 ).…”

“…CMA 6.9 was from the Collection of Environmental Microorganisms of the Laboratory of Environmental Microbiology of the State University of Ponta Grossa (UEPG). This collection consists of 67 bacterial biofilm isolates from water storage tanks used to wash agrochemical packaging ( Lima et al, 2020 ) at the BASF experimental station, Fazenda Escola Capão da Onça of UEPG.…”

“…The genus Pseudomonas stands out for its tolerance to chemical stressors because of its metabolic and physiological versatility, and it can be isolated from soil, fresh water, biofilms, and other places, with potential for application in bioremediation ( Venturi, 2006 ; Karami et al, 2016 ; Melo et al, 2016 ). Lima et al (2020) obtained collections of bacteria capable of tolerating different herbicides, including Pseudomonas sp. CMA 6.9, assessed in this study.…”

Herbicide bioremediation: from strains to bacterial communities

“…The predicted metagenomics bioinformatics analysis was used in biofilm and planktonic communities in reservoirs containing herbicide-contaminated wastewater to characterize important genes, which functions were relevant for survival in these environments, by performing only 16S rDNA amplicon next-generation sequencing, and analyzing the genes present in the identified OTUs. With this technique it was possible to identify genes functions related to biofilm formation and structure, membrane transport, quorum sensing and xenobiotic degradation ( Lima et al., 2020 ).…”