Title | An integrated network analysis identifies how ArcAB enables metabolic oscillations in the nitric oxide detoxification network of Escherichia coli. |
Publication Type | Journal Article |
Year of Publication | 2017 |
Authors | Sacco, SA, Adolfsen, KJ, Brynildsen, MP |
Journal | Biotechnol J |
Volume | 12 |
Issue | 8 |
Date Published | 2017 Aug |
ISSN | 1860-7314 |
Keywords | Aerobiosis, Bacterial Outer Membrane Proteins, Catalysis, Escherichia coli, Escherichia coli Proteins, Gene Expression Regulation, Bacterial, Inactivation, Metabolic, Membrane Proteins, Nitric Oxide, Oxygen, Oxygenases, Protein Kinases, Repressor Proteins |
Abstract | <p>The virulences of many pathogens depend on their abilities to detoxify the immune antimicrobial nitric oxide (NO•). The functions of bacterial NO• detoxification machinery depend on oxygen (O ), with O inhibiting some enzymes, whereas others use it as a substrate. Previously, Escherichia coli NO• detoxification was found to be highly attenuated under microaerobic conditions and metabolic oscillations were observed. The oscillations in [NO•] and [O ] were found to result from the inhibitory action of NO• on aerobic respiration, the catalytic inactivation of NO• by Hmp (an NO• dioxygenase), and an imbalanced competition for O between Hmp and cytochrome terminal oxidase activity. Here the authors investigated the role of the ArcAB two component system (TCS) in microaerobic NO• detoxification. The authors observed that wild-type, ΔarcA, and ΔarcB had comparable initial NO• clearance times; however, the mutant cultures failed to exhibit [NO•] and [O ] oscillations. Using an approach that employed experimentation and computational modeling, the authors found that the loss of oscillations in ΔarcA was due to insufficient induction of cytochrome bd-I expression. Collectively, these results establish ArcAB as a TCS that influences NO• detoxification in E. coli within the physiologically-relevant microaerobic regime.</p> |
DOI | 10.1002/biot.201600570 |
Alternate Journal | Biotechnol J |
PubMed ID | 28449226 |