Microbial degradation of glyphosate herbicides (Review)

Свиридов, А. В.; Shushkova, T. V.; Ermakova, I. T.; Иванова, Е. В.; Epiktetov, D. O.; Leontievsky, A. A.

doi:10.1134/s0003683815020209

Cited by 201 publications

(79 citation statements)

References 60 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As biological degradation of GPS in soils is expected to occur over the time period in which these studies were conducted [44], efforts were made to quantify the amount of the primary metabolite (AMPA) in the residual extracts. A lack of prolonged measured radioactivity in the effluent solution suggests that the 14 C remains associated with the highly reactive phosphonomethyl functional group, indicating that the dominant mechanism of microbial degradation is through the AMPA pathway, consistent with the findings of others [44,52]. Assuming that degradation beyond AMPA will result in a metabolite lacking the phosphonomethyl group and, therefore, a compound that will be readily mineralized to 14 CO 2 , all measured radioactivity in the extracting solution is taken to be either GPS or AMPA.…”

Section: Distribution In the Soil Columnsupporting

confidence: 88%

Glyphosate Transport in Two Louisiana Agricultural Soils: Miscible Displacement Studies and Numerical Modeling

Padilla

Selim

2018

Soil Systems

View full text Add to dashboard Cite

Glyphosate (N-(phosphonomethyl) glycine) (GPS) is currently the most commonly used herbicide worldwide, and is generally considered as immobile in soils. However, numerous reports of the environmental occurrence of the herbicide coupled with recent evidence of human toxicity necessitate further investigation as to the behavior of GPS in the soil environment. Batch sorption studies along with miscible displacement experiments were carried out in order to assess the mobility of GPS in two Louisiana agricultural soils; Commerce silt loam and Sharkey clay. Batch results indicated a high affinity of both soils for solvated GPS, with greater affinity observed by the Sharkey soil. GPS sorption in the Commerce soil was most likely facilitated by the presence of amorphous Fe and Al oxides, whereas the high cation exchange capacity of the Sharkey soil likely allows for GPS complexation with surface exchangeable poly-valent cations. Miscible displacement studies indicate that GPS mobility is highly limited in both soils, with 3% and 2% of the applied herbicide mass recovered in the effluent solution from the Commerce and Sharkey soils, respectively. A two-site multi-reaction transport model (MRTM) adequately described GPS breakthrough from both soils and outperformed linear modeling efforts using CXTFIT. Analysis of extracted herbicide residues suggests that the primary metabolite of GPS, aminomethylphosphonic acid (AMPA), is more mobile in both soils, although both compounds are strongly retained.

show abstract

Section: Distribution In the Soil Columnsupporting

confidence: 88%

Glyphosate Transport in Two Louisiana Agricultural Soils: Miscible Displacement Studies and Numerical Modeling

Padilla

Selim

2018

Soil Systems

View full text Add to dashboard Cite

show abstract

“…Finally, many bacteria can survive in the presence of glyphosate because they are able to degrade and/or use the herbicide as a source of phosphorous ( Fig. 8) (Pipke et al, 1980;Shinabarger and Braymer, 1986;Fitzgibbon and Braymer, 1988;Liu et al, 1991;Dick and Quinn, 1995;Penaloza-Vazquez et al, 1995;Singh and Walker, 2006;Castro Jr. et al, 2007;Sviridov et al, 2011Sviridov et al, , 2015Hove-Jensen et al, 2014;Kryuchkova et al, 2014). To conclude, several mechanisms of glyphosate resistance have been described over the past years and novel mechanisms allowing survival in the presence of the herbicide are certainly identified in the future.…”

Section: Discussionmentioning

confidence: 99%

Identification of the first glyphosate transporter by genomic adaptation

Wicke

Schulz

Lentes

et al. 2019

Environmental Microbiology

View full text Add to dashboard Cite

Summary The soil bacterium Bacillus subtilis can get into contact with growth‐inhibiting substances, which may be of anthropogenic origin. Glyphosate is such a substance serving as a nonselective herbicide. Glyphosate specifically inhibits the 5‐enolpyruvyl‐shikimate‐3‐phosphate (EPSP) synthase, which generates an essential precursor for de novo synthesis of aromatic amino acids in plants, fungi, bacteria and archaea. Inhibition of the EPSP synthase by glyphosate results in depletion of the cellular levels of aromatic amino acids unless the environment provides them. Here, we have assessed the potential of B. subtilis to adapt to glyphosate at the genome level. In contrast to Escherichia coli, which evolves glyphosate resistance by elevating the production and decreasing the glyphosate sensitivity of the EPSP synthase, B. subtilis primarily inactivates the gltT gene encoding the high‐affinity glutamate/aspartate symporter GltT. Further adaptation of the gltT mutants to glyphosate led to the inactivation of the gltP gene encoding the glutamate transporter GltP. Metabolome analyses confirmed that GltT is the major entryway of glyphosate into B. subtilis. GltP, the GltT homologue of E. coli also transports glyphosate into B. subtilis. Finally, we found that GltT is involved in uptake of the herbicide glufosinate, which inhibits the glutamine synthetase.

show abstract

“…Several factors are associated with the rate and magnitude of GPS degradation, such as total microbial biomass (Franz et al, 1997;Rueppel et al, 1977) and the presence of specific microbial species (Gimsing et al, 2004b). Since GPS degradation in soils is mainly attributed to biotic processes (Sviridov et al, 2015), either general microbial activity is greater in the Sharkey soil or population dynamics are such that sorbed-phase GPS is more readily bioavailable.…”

Section: Glyphosate Dissipationmentioning

confidence: 99%

Time‐Dependent Sorption and Desorption of Glyphosate in Soils: Multi‐reaction Modeling

Padilla

Selim

2019

Vadose Zone Journal

View full text Add to dashboard Cite

Core Ideas Batch data were successfully described by a multi‐reaction model. A single set of parameters can be applied to a range of concentrations. Glyphosate was strongly retained and readily degraded in both soils. The herbicide glyphosate [N‐(phosphonomethyl) glycine] (GPS) is commonly found offsite of application areas, despite traditional presumptions of the compound's immobility in the environment. This suggests that further efforts to predict the behavior and fate of GPS in soils are needed. In this study, kinetic batch experiments were conducted to assess the time‐dependent sorption and desorption of GPS by two agricultural soils from southern Louisiana: Commerce silt loam (a fine‐silty, mixed, superactive, nonacid, thermic Fluvaquentic Endoaquept) and Sharkey clay (a very‐fine, smectitic, thermic Chromic Epiaquert). Results of batch experiments indicate a high affinity of both soils for GPS, with 24‐h Freundlich coefficients of 158 and 396 Ln mg1−n kg−1 for the Commerce and Sharkey soils, respectively. An apparent time dependency of GPS sorption by both soils was observed, especially within the first 72 h. Changes in solution concentrations of the herbicide beyond 72 h are attributed to both additional sorption as well as solution‐phase degradation. A two‐site multi‐reaction model incorporating time‐dependent reversible and irreversible reactions successfully described the measured data from the batch experiments. However, values of the rate coefficients and sorbed concentrations may be overestimated due to the model's inability to account for degradation processes. Analysis of extracted soil‐bound residues illustrates that degradation of sorbed phase GPS is significant in both soils, although it occurs to a greater extent in the Sharkey soil. Degradation of the herbicide probably occurs through the aminomethylphosphonic acid pathway, as 14C remained associated with the phosphonomethyl group. Models that account for both time‐dependent reactions and degradation will probably lead to improved predictions of the fate of GPS in soils.

show abstract

Microbial degradation of glyphosate herbicides (Review)

Cited by 201 publications

References 60 publications

Glyphosate Transport in Two Louisiana Agricultural Soils: Miscible Displacement Studies and Numerical Modeling

Glyphosate Transport in Two Louisiana Agricultural Soils: Miscible Displacement Studies and Numerical Modeling

Identification of the first glyphosate transporter by genomic adaptation

Time‐Dependent Sorption and Desorption of Glyphosate in Soils: Multi‐reaction Modeling

Contact Info

Product

Resources

About