Journal Article

Toxicity of 2,4-dichlorophenoxyacetic acid to Rhizobium sp in pure culture

Fabra, A. (Universidad Nacional de Rio Cuarto, Rio Cuarto Cordoba, Argentina.), Duffard, R, Evangelista de Duffard, A

1997

Overview

The toxicity of 2,4-D toward Rhizobium sp. was investigated on three levels: on stationary-phase Rhizobium sp. culture, in terms of its distribution in the prokaryotic cell, and in terms of irreversible binding to macromolecules. Results indicated that exposure to 1 mM 2,4-D in the stationary phase caused diminution in the optical density, which indicated a process of cell lysis. The lethal concentration of 2,4-D was determined to be 2.5 mM, and pregrowth of the bacteria in 1 mM 2,4-D for 12 h was not enough to produce adaptation to the lethal concentration. However, at a 2,4-D concentration of 1 mM, Rhizobium sp. were able to utilize the herbicide as a sole source of carbon. The highest 2,4-D concentration was always detected in the cell wall, suggesting that it acts as a permeability barrier to 2,4-D intracellular incorporation. Binding of 2,4-D to lipids and protein was found to be irreversible.

• Publisher: Springer-Verlag,Springer Nature B.V
• Subject: 2,4-D / 2,4-Dichlorophenoxyacetic Acid / 2,4-Dichlorophenoxyacetic Acid - metabolism / 2,4-Dichlorophenoxyacetic Acid - toxicity / agrochemicals / Agronomy. Soil science and plant productions / Bacterial Proteins / Bacterial Proteins - metabolism / Biological and medical sciences / Cells, Cultured / Culture Media / drug effects / Fundamental and applied biological sciences. Psychology / Herbicides / Herbicides - metabolism / Herbicides - toxicity / Lipid Metabolism / metabolism / pesticides / plant nutrition / Protein Binding / RHIZOBIUM / Rhizobium - drug effects / Rhizobium - metabolism / Soil and water pollution / Soil science / Spheroplasts / Spheroplasts - drug effects / Spheroplasts - metabolism / Time Factors / TOXICIDAD / TOXICITE / TOXICITY