Maybe Nitrobacter is not the main nitrite oxidizer in wastewater - Meet Nitrospira the main NOB seen in Aster Bio's DNA based wastewater testing

NITROSPIRA SP
Bergey’s Manual
Nitrospira make up the key nitrite-oxidizing bacteria in most wastewater treatment systems. While a lot of the literature highlights Nitrobacter, Nitrospira generally grow best on (very) low levels of nitrite found in WWTPs. Nitrobacter, on the other hand, likes higher nitrite concentrations and is easier to grow in the lab.

• Gram-negative
• Aerobic
• Some strains can use nitrate as a terminal electron acceptor

And, surprisingly, some strains of Nitrospira are Complete AMMonia OXidizers (COMAMMOX) capable of both ammonia and nitrite oxidation. In some WWTPs with significant ammonia nitrogen loadings, we have seen high levels of Nitrospira and extremely low levels of Nitrosomonas or other known ammonia-oxidizing bacteria. Using polymerase chain reaction assays (PCR), we can identify COMAMMOX strains present in some MLSS samples.