Mechanisms and Control of xlink="http://www.w3.org/1999/xlink" xlink:href="00330-ilm01.gif"/> Inhibition of Anaerobic Ammonium Oxidation (Anammox)

Nitrite (), one of the main substrates in the anaerobic ammonium oxidation (anammox) process, has the potential to inhibit anammox bacteria. The sensitivity of anammox cells with different energy status to was evaluated, and addition of nitrate ( inhibition on the basis of narK gene with the putative function of facilitating / antiporter. The results showed that the resistance of anammox bacteria to inhibition follows the order: active-cells > starved-cells > resting-cells > starved-/resting-cells. Anammmox resting cells have increasing tolerance to in the pH range from 7.0 to 7.5. Dissipating the proton gradient by using carbonyl cyanide m-chlorophenyl hydrazine (CCCP) caused severe inhibition at all pH values including pH = 7.5. Addition of enabled activity recovery of -inhibited anammox bacteria regardless of whether the proton gradient was disrupted or not, supporting the hypothesis of -dependent detoxification via a secondary transport system.