A traditional defining characteristic of members of the Shewanella genus is the inability to use glucose as a substrate for growth. Shewanella spp. isolates, however, have the common ability to use a diverse array of substrates, allowing them to survive in a range of environments (Hau & Gralnick, 2007; Fredrickson et al.,

2008). Members of the Shewanella genus show great flexibility with regard to alteration of growth strategy and metabolism based on the availability of different carbon sources (Tang et al., 2009). In keeping with this flexibility, the traditional view of inability to use glucose has changed as many Shewanella spp. isolates have since been found to use glucose (Bowman et al., 1997; Nogi et al., 1998; Leonardo et al., 1999; Brettar et al., 2002; Gao et al., 2006; Zhao et al., 2006; Xiao et al., 2007; Rodionov et al., 2010). To this end, Shewanella oneidensis selleckchem MR-1, isolated from sediment in Lake Oneida, NY, has not been yet observed to use glucose as a fermentation substrate, under short-term growth experiments without initial glucose exposure in a rich growth medium (Myers & Nealson, 1988; Venkateswaran et al., 1999; Rodionov et al., 2010). In microbial fuel cells (MFCs) with complex

growth media, however, S. oneidensis Tamoxifen in vitro has been found to generate current upon extended glucose addition (Biffinger et al., 2008, 2009). This response to glucose addition was slow, suggesting that S. oneidensis may be able to use glucose, given ample time to induce the appropriate genetic mechanisms, for a mutator population to proliferate (Chao & Cox, 1983; Giraud et al., 2001a, b) and/or

develop a ‘growth advantage in stationary phase’ (GASP) mutant (Finkel & Kolter, 1999). Mutator bacteria contain mutations that inactivate mutation-avoidance genes yielding higher spontaneous mutation rates, which in turn yield an increased evolutionary pace (Chao & Cox, 1983; Mao et al., 1997; Giraud et al., 2001a, b). GASP refers to the genetic alterations (not physiological adaptations) that occur in cells incubated in long-term batch cultures that confer a competitive advantage to these cells over younger ‘naïve’ cultures (Finkel, 2006). Given that the S. oneidensis genome suggests the ability to use glucose as a Liothyronine Sodium fermentation substrate via the Entner–Doudoroff pathway, the current study seeks to show whether S. oneidensis can indeed utilize glucose as a sole carbon source given an initial glucose exposure, as suggested by previous MFC studies (Biffinger et al., 2008, 2009). Shewanella oneidensis MR-1 (Venkateswaran et al., 1999), obtained from the American Type Culture Collection (ATCC#700550) and stored at −80 °C, was grown up in Luria–Bertani (LB) broth for 24 h, shaking (100 r.p.m.) at 25 °C. From the LB culture, S. oneidensis MR-1 was serially passed every 24 h for 96 h into LB broth amended with 10 mM glucose.