Confocal micrographs of FISH-stained Nitrotoga-like bacteria in activated sludge samples from WWTPs Bad Zwischenahn. Probes FGall221b (red) and EUB338mix (blue) at high magnification. Nitrotoga appears magenta. Scale bar = 10 microns. - Source:2Chemoautotroph/Mixotroph
"Candidatus Nitrotoga" are nitrite oxidizing bacteria that are abundant in some plants. In some cases they are the only detectable NOB present 2 1. They possess an aerobic chemolithotroph metabolism with oxidation of nitrite to nitrate. Carbon dioxide is used as the sole carbon source 3 2. The nitrate-oxidizing activity of all characterized enriched "Ca. Nitrotoga" members is suggested to be more favorable under cold temperature, except the first isolate "Ca. Nitrotoga fabula" which has temperature optimum at 24 - 28 °C 6. Moreover, a slightly acidic pH (5.7 to 6.8) and elevated nitrite loading were reported to favor growth of "Ca." Nitrotoga" over Nitrospira* 7 8 9.
The first isolate "Ca. Nitrotoga fabula" and several enriched "Ca. Nitrotoga" members 6
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