Growth rate influences reductive biodegradation of the organophosphorus pesticide demeton by Corynebacterium glutamicum

    loading  Checking for direct PDF access through Ovid


The organophosphorous pesticide, demeton-S-methyl was transformed by Corynebacterium glutamicum in co-metabolism with more readily degradable substrates. Glucose, acetate and fructose were tested as growth substrates, and the highest demeton-S-methyl biotransformation average rate (0.78 mg l−1 h−1) and maximum instantaneous rate (1.4 mg l−1 h−1) were achieved on fructose. This higher efficiency seems to be linked to the atypical behavior of C. glutamicum grown on fructose, characterized by a prolonged period of accelerating growth instead of a constant growth rate observed on glucose or acetate. More precisely, for growth rates in the 0.1–0.4 h−1 range, a direct coupling between the specific demeton-S-methyl consumption rate and the growth rate was demonstrated on fructose during batch –, steady state continuous – or continuous cultures with a controlled transient growth rate (accelerostat technology). The demeton-S-methyl biotransformation was more favoured during an acceleration phase of the growth rate.

    loading  Loading Related Articles