Cation transport by the respiratory NADH: quinone oxidoreductase (complex I): facts and hypotheses (biochemsoctrans.org)
The idea is not as odd as it may sound; scientists studying other environments have previously observed nitrite oxidoreductase working in reverse when microbial growth is inhibited. (eos.org)
Glutaredoxins (GRXs) are ubiquitous oxidoreductases implicated in redox homeostasis that catalyze the reversible reduction of disulfide bonds. (biologie.uni-osnabrueck.de)