In-vitro biodegradation of Glyphosate using genetically improved bacterial isolates from ‎highly polluted wastewater

Document Type : Original Article

Authors

1 Department of Microbial Genetics, National Research Centre, Dokki, Giza, Egypt.

2 Department of Plant Protection, Faculty of Agriculture, Ain Shams University, Cairo, Egypt.

Abstract

Due to the problems assigned by unregulated and indiscriminate applications of ‎pesticides, adverse effects to human health, different life forms, and ecosystems were ‎evolved. Development of technologies that guarantee their elimination in a safe, efficient, ‎and economical way is important, among these strategies, bioremediation that overcomes ‎the limitations of traditional methods for the disposal of hazardous compounds. An ‎organophosphorus pesticide, Glyphosate (N-phosphono methyl glycine), was the most ‎persistent pesticide in the Al-Jabal Al-Asfar drain water canal. Four bacterial isolates ‎recorded a notable degradation behavior toward glyphosate with various capabilities. The ‎PCR amplification of the 16s rDNA gene was employed to identify these bacterial ‎isolates. They were identified as Bacillus cereus NRC1-PP, Pseudomonas alcaligenes ‎NRC2-Gly, Pseudomonas stutzeri NRC3-8PS, and Bacillus licheniformis NRC4-1BL and ‎deposited at GenBank. Bacillus cereus NRC1-PP, as the highest degrader, biodegraded ‎‎28.96% of glyphosate when injected in minimal salt media after ten days. Enhancement ‎of Glyphosate biodegradation potential for Bacillus cereus NRC1-PP through physical ‎mutagen UV radiation and chemical mutagen Ethyl methane sulfonate (EMS) was ‎implemented. The biodegradation fitness was increased to 2.5-fold in UV-10 bacterial ‎mutant. Protein profiles of Bacillus cereus NRC1-PP and its mutants were investigated ‎by SDS-PAGE. Dendrogram of SDS-PAGE based on unweighted pair group method ‎with arithmetic averages algorithm (UPGMA) divided and categorized into 2 main ‎clusters according to similarity coefficient. The enzymatically- generated degradation ‎products of Glyphosate by GC/MS were detected. The treated samples were presented 12 ‎metabolites were detected in the case of UV-10 treatment; however, only presented 7 ‎metabolites were assigned in the untreated sample (control). These metabolites included ‎amino methyl phosphonic, and new ions such as C2N2O and C3H4O3P. The results of this ‎study indicate that bacterial isolate and their mutants are good candidates for Glyphosate ‎biodegradation in safe and efficient behavior

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Volume 65, Issue 13 - Serial Number 13
Special Issue: Chemistry and Global Challenges
December 2022
  • Receive Date: 29 May 2022
  • Revise Date: 28 June 2022
  • Accept Date: 28 June 2022
  • First Publish Date: 28 June 2022