Abstract The discovery of nitrogen fixation in unicellular cyanobacteria provided the first clues for the existence of a circadian clock in prokaryotes. However. recalcitrance to genetic manipulation barred their use as model systems for deciphering the clock function. Here. https://www.alarecre.com/NHL-Dallas-Stars-Black-Background-iPhone-13-Pro-Max-MagSafe-Case-p96318/