Aerobic and Facultatively Anaerobic Organisms

An issue of particular relevance in the context of bioremediation is illustrated by the increased rate of cell death in an established naphthalene-degrading Pseudomonas putida G7 brought about by the substrate (naphthalene) under conditions of oxygen (or combined oxygen and nitrogen) limitation (Ahn et al. 1998). 

The growth of Bacillus subtilis may take place under a variety of conditions (a) aerobic conditions, (b) using nitrate as electron acceptor, and (c) fermentative conditions with glucose provided pyruvate is available as an electron acceptor since the organism lacks pyruvate formate hydrogen lyase (Nakano and Zuber 1998). 

Thauera sp. strain DNT-1 is able to degrade toluene under aerobic conditions mediated by a dioxygenase, and under denitrifying conditions in the absence of oxygen by the anaerobic benzylsuccinate pathway (Shinoda et al. 2004). Whereas the tod genes were induced under aerobic conditions, the bss genes were induced under both aerobic and anaerobic conditions. 

It should also be appreciated that the oxygen concentration may determine the outcome of a reaction, or even the possibility of either oxidative or reductive reactions  

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