Experimental Evidence for Manure-Borne Bacteria Invasion in Soil During a Coalescent Event: Influence of the Antibiotic Sulfamethazine.

The fertilization of agricultural soil by organic amendment that may contain antibiotics, like manure, can transfer bacterial pathogens and antibiotic-resistant bacteria to soil communities. However, the invasion by manure-borne bacteria in amended soil remains poorly understood. We hypothesized that this kind of process is both influenced by the soil properties (and those of its microbial communities) and by the presence of contaminants such as antibiotics used in veterinary care.

Contrasting Effects of Environmental Concentrations of Sulfonamides on Microbial Heterotrophic Activities in Freshwater Sediments.

The sulfonamide antibiotics sulfamethoxazole (SMX) and sulfamethazine (SMZ) are regularly detected in surface sediments of contaminated hydrosystems, with maximum concentrations that can reach tens of μg kg in stream and river sediments. Little is known about the resulting effects on the exposed benthic organisms. Here we investigated the functional response of stream sediment microbial communities exposed for 4 weeks to two levels of environmentally relevant concentrations of SMX and SMZ, tested individually.

Antibiotrophy: Key Function for Antibiotic-Resistant Bacteria to Colonize Soils-Case of Sulfamethazine-Degrading sp. C448.

Chronic and repeated exposure of environmental bacterial communities to anthropogenic antibiotics have recently driven some antibiotic-resistant bacteria to acquire catabolic functions, enabling them to use antibiotics as nutritive sources (antibiotrophy). Antibiotrophy might confer a selective advantage facilitating the implantation and dispersion of antibiotrophs in contaminated environments. A microcosm experiment was conducted to test this hypothesis in an agroecosystem context.

Complete Genome Sequences of Four Atrazine-Degrading Bacterial Strains, sp. Strain ADPe, sp. Strain TES, sp. Strain 38R, and sp. Strain SR38.

We report here the complete genome sequences of four atrazine-degrading bacteria. Their genomes will serve as references for determining the genetic changes that have occurred during an evolution experiment.

Labour sharing promotes coexistence in atrazine degrading bacterial communities.

Microbial communities are pivotal in the biodegradation of xenobiotics including pesticides. In the case of atrazine, multiple studies have shown that its degradation involved a consortia rather than a single species, but little is known about how interdependency between the species composing the consortium is set up. The Black Queen Hypothesis (BQH) formalized theoretically the conditions leading to the evolution of dependency between species: members of the community called 'helpers' provide publicly common goods obtained from the costly degradation of a compound, while others called 'beneficiaries' take advantage of the public goods, but lose access to the primary resource through adaptive degrading gene loss.

Environmental risk assessment of antibiotics in agroecosystems: ecotoxicological effects on aquatic microbial communities and dissemination of antimicrobial resistances and antibiotic biodegradation potential along the soil-water continuum.

Antibiotics have a wide application range in human and veterinary medicines. Being designed for pharmacological stability, most antibiotics are recalcitrant to biodegradation after ingestion and can be persistent in the environment. Antibiotic residues have been detected as contaminants in various environmental compartments where they cause human and environmental threats, notably with respect to the potential emergence and proliferation of antibiotic-resistant bacteria.