Transcriptome profiling of cells initially attached to different surfaces

Initial attachment to a surface marks the onset of a bacterial life style switch from planktonic to biofilm mode of growth. Among dissimilatory iron reducing bacteria, S. oneidensis MR-1 is notable due to its extensive respiratory versatility. It has been hypothesized that direct interaction of Shewanella cells with, or close proximity to, an appropriate surface facilitates the deposition of electrons. In fact, Shewanella species have been demonstrated to adhere to various surfaces and form biofilms. Global transcriptome profiling was performed on cells in the transition to surface-associated growth using different surfaces and conditions to understand molecular mechanisms underlying the initiation of microbe-surface interactions and the switch from planktonic to sessile life style. In the study presented, expression profiles of two independent replicates of Shewanella oneidensis MR-1 wild type cells attached to glass for 0.25 h and 1 h, respectively, under hydrodynamic conditions were compared to two independent replicates of planktonic grown Shewanella oneidensis MR-1 wild type cells. Furthermore, expression profiles of two independent replicates of Shewanella oneidensis MR-1 wild type cells attached for 1 h to iron surface under hydrodynamic conditions were compared to two independent replicates of Shewanella oneidensis MR-1 wild type cells attached to glass for 1 h. All samples were obtained from aerobically grown cells in LM.