This tendency to exhibit similar responses suggests that the phen

This tendency to exhibit similar responses suggests that the phenomena observed here represent fundamental ways that bacteria respond to these conditions. Consistency in HM781-36B findings across studies in basic responses (for Evofosfamide concentration example, higher cell numbers under MRG) are supportive of this idea [e.g., [26, 27, 47, 48]], but additional comparative studies are needed to determine if these trends hold. Our observation of higher

bacterial numbers (at stationary phase) under MRG conditions is in agreement with observations made by other researchers [e.g. [26, 27, 47, 48]] and suggests that under MRG conditions, lack of sedimentation results in uniform cell distribution throughout the vessel and bacteria having higher accessibility to nutrients thus leads to higher final densities. Differences in bacterial numbers observed in our study depended on the growth medium and growth phase; significant differences between MRG and NG were observed under nutrient poor conditions. Bacteria respond to nutrient

limitation by reducing biovolume (i.e., by undergoing reductive cell division that increases surface-to-volume ratio) [9, 49] and protein synthesis [10]. However, no significant differences in bacterial biovolume (except for smaller average S. aureus volumes under MRG at exponential phase in dilute LB) and see more protein amounts per cell were found under MRG conditions when Ibrutinib mouse compared to NG conditions. These findings suggest that nutrient limitation, caused by depletion of nutrients in microenvironments around the cells under MRG, was not a significant factor influencing responses. Membrane potential (MP) is required

for a variety of cellular processes, such as ATP synthesis [50], nutrient transport [51], and chemotaxis [52]. In addition, MP is required for survival under stressful conditions, such as exposure to low pH [53] or antibiotics [54, 55]. Accordingly, MP is one of the best studied physiological functions in bacteria under a variety of stressful environmental conditions [56–58]. In our study, higher MP values were found under MRG conditions for E. coli and S. aureus in LB and dilute LB, respectively, and this response was limited to stationary phase. However, E. coli grown in M9 minimal media and S. aureus grown in LB did not differ in their MP between MRG and NG conditions. This observation is consistent with expectations since MP varies with availability of nutrients [36, 57]. We found higher average MP under MRG conditions suggesting that bacterial membranes were more energized under these conditions and which may be due to even distribution of cells that results in higher accessibility of nutrients.

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