Shallow breathing: Bacterial life at low O 2

1] Department of Microbiology and Molecular Genetics, 6180 Biomedical Physical Sciences, Michigan State University, East Lansing, Michigan 48824, USA. [2] Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109, USA.
Nature Reviews Microbiology (Impact Factor: 23.57). 03/2013; 11(3):205-12. DOI: 10.1038/nrmicro2970
Source: PubMed


Competition for molecular oxygen (O(2)) among respiratory microorganisms is intense because O(2) is a potent electron acceptor. This competition leads to the formation of microoxic environments wherever microorganisms congregate in aquatic, terrestrial and host-associated communities. Bacteria can harvest O(2) present at low, even nanomolar, concentrations using high-affinity terminal oxidases. Here, we report the results of surveys searching for high-affinity terminal oxidase genes in sequenced bacterial genomes and shotgun metagenomes. The results indicate that bacteria with the potential to respire under microoxic conditions are phylogenetically diverse and intriguingly widespread in nature. We explore the implications of these findings by highlighting the importance of microaerobic metabolism in host-associated bacteria related to health and disease.

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