Mineralization of the herbicide atrazine as a carbon source by a Pseudomonas strain.
Strain YAYA6 was isolated from a mixed microbial community that was growing on atrazine as a sole carbon source and formed quantitative amounts of chloride and nitrate. This strain was identified as a member of the true pseudomonad group (RNA group I) and was given the designation DMS 93-99. The growth yield when atrazine was the sole carbon and nitrogen source was 80 g (dry weight) of cells per mol of atrazine, and the cell doubling time was around 11 h. Approximately 20% of [U-ring 14C]atrazine was mineralized during primary degradation of atrazine. After atrazine disappeared from the culture supernatant, mineralization continued until the level of mineralization was more than 50%. Under different experimental conditions 10% of the atrazine supplied initially was converted to cyanuric acid and < 1% was converted to other s-triazines after prolonged incubation. Degradation proceeded via dechlorination and N-dealkylation. Atrazine was degraded until the concentration was circa 0.1 milligrams/liter. We obtained evidence showing that strain YAYA6 has specific uptake mechanisms for atrazine but less specific degradation mechanisms for s-triazines.
Yanze-Kontchou
C
C
Environmental Process Technology, Ciba-Geigy AG, CH-4133 Schweizerhalle, Switzerland.
Gschwind
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N
D001280:Atrazine / Q000378:metabolism*; D001673:Biodegradation, Environmental; D003470:Culture Media; D011549:Pseudomonas / Q000302:isolation & purification / Q000378:metabolism*; D012988:Soil Microbiology; D014227:Triazines / Q000378:metabolism
D003470:Culture Media; D014227:Triazines; D001280:Atrazine