Assembly of an atrazine catabolic operon and its introduction to Gram-negative hosts for robust and stable degradation of triazine herbicides
Autor: | Everardo Curiel-Quesada, Fernando Martínez, Alfredo Lazarini-Martínez, Abigail Pérez-Valdespino, Juvencio Galíndez-Mayer, Nora Ruiz Ordaz, Cleotilde Juárez-Ramírez |
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Rok vydání: | 2019 |
Předmět: |
Operon
Transposases Polymerase Chain Reaction Microbiology 03 medical and health sciences chemistry.chemical_compound Plasmid Transcription (biology) Pseudomonas Gram-Negative Bacteria Genetics Atrazine Insertion sequence Molecular Biology Gene Chromatography High Pressure Liquid Soil Microbiology 030304 developmental biology 0303 health sciences biology Herbicides Triazines 030306 microbiology biology.organism_classification Biochemistry chemistry Bacteria |
Zdroj: | FEMS Microbiology Letters. 366 |
ISSN: | 1574-6968 0378-1097 |
Popis: | In 1995, Pseudomonas sp. ADP, capable of metabolizing atrazine, was isolated from contaminated soil. Genes responsible for atrazine mineralization were found scattered in the 108.8 kb pADP-1 plasmid carried by this strain, some of them flanked by insertion sequences rendering them unstable. The goal of this work was to construct a transcriptional unit containing the atz operon in an easy to transfer manner, to be introduced and inherited stably by Gram-negative bacteria. atz genes were PCR amplified, joined into an operon and inserted onto the mobilizable plasmid pBAMD1–2. Primers were designed to add efficient transcription and translation signals. Plasmid bearing the atz operon was transferred to different Gram-negative strains by conjugation, which resulted in Tn5 transposase-mediated chromosomal insertion of the atz operon. To test the operon activity, atrazine degradation by transposants was assessed both colorimetrically and by high-performance liquid chromatography (HPLC). Transposants mineralized atrazine more efficiently than wild-type Pseudomonas sp. ADP and did not accumulate cyanuric acid. Atrazine degradation was not repressed by simple nitrogen sources. Genes conferring atrazine-mineralizing capacities were stable and had little or null effect on the fitness of different transposants. Introduction of catabolic operons in a stable fashion could be used to develop bacteria with better degrading capabilities useful in bioremediation. |
Databáze: | OpenAIRE |
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