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Updated: Jun 5, 2026

Creating Rapid Oxygen Oscillations in Microbial Single-cell Growth Analysis using a Microfluidic Double-layer Device
Published on: July 18, 2025
Oxygen control of nitrogen oxide respiration, focusing on α-proteobacteria
1Department of Microbiology, Cornell University, Ithaca, NY 14853, USA. jps2@cornell.edu
Abstract:
Denitrification is generally considered to occur under micro-oxic or anoxic conditions. With this in mind, the physiological function and regulation of several steps in the denitrification of model α-proteobacteria are compared in the present review. Expression of the periplasmic nitrate reductase is quite variable, with this enzyme being maximally expressed under oxic conditions in some bacteria, but under micro-oxic conditions in others. Expression of nitrite and NO reductases in most denitrifiers is more tightly controlled, with expression only occurring under micro-oxic conditions. A possible exception to this may be Roseobacter denitrificans, but the physiological role of these enzymes under oxic conditions is uncertain.
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