It doesn't need oxygen

Usage examples of anaerobe.

I understood, would consist of engineered microbes, their genetic material spliced together from bacteria discovered inside rocks in the dry valleys of Antarctica, from anaerobes capable of surviving in the outflow pipes of nuclear reactors, from unicells recovered from the icy sludge at the bottom of the Barents Sea.

I can reply is even the most rugged, xenophile, radiation-resistant cryophilic anaerobes we can imagine are going to have a hard time maintaining more than a toehold on current-day Mars, spending most of their time in a non-metabolic, frozen state, waiting for the times when conditions are right and water can be briefly liquid on the surface.

The exotoxin from this particular anaerobe was quite as deadly as I had said but, fortunately, Otto had been unaware that the incubation period was seldom less than four hours and, in extreme cases, had been known to be as long as forty-eight-not that the period of incubation delay made the final results any less fatal.