Another possibility that remains to be explored is whether the hfq mutant’s sensitivity to oxidative stress is due to altered function of superoxide dismutase (sodB – So_2881) and/or one or more of the four genes predicted DNA Damage inhibitor to encode proteins with catalase activity katB (So_1070), So_1771.2, katG2 (So_4405), and katG1 (So_0725)] [12]. Finally, it will be of interest to determine whether S. oneidensis contains an hfq-dependent OxyR-OxyS system that is involved
in response to oxidative stress as in other systems [20, 31]. We are currently investigating the mechanisms by which S. oneidensis Hfq promotes growth, terminal culture density, and stationary phase survival. However, given that Hfq has been broadly implicated in the function of many sRNAs in other systems [32], the S. oneidensis hfq mutant generated in this study will facilitate analysis of the roles of Hfq and sRNAs in adaptation to a wide range of environmental conditions. This is of particular interest since a previous study demonstrated that S. oneidensis sRNAs do not always have completely overlapping functions with their homologs in other systems [33]. Acknowledgements We thank Aixia Zhang for supplying the anti-Hfq antibody. Thanks to Fr. Nicanor Austriaco, O.P. and Jennifer Gervais for thoughtful discussions and critical reading of the manuscript. Research reported in this publication was supported by an Institutional Development Award (IDeA) from the
National Institute of General Medical Sciences of Peptide 17 molecular weight the National Institutes of Health under grant number 8 P20 GM103430-12. Additional
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