Transcriptomic analysis of chlorhexidine shock in Acinetobacter baumannii. Acinetobacter baumannii

In this study the transcriptomic changes occurring in A. baumannii ATCC 17978 in response to shock treament using the biocide chlorhexdine were determined. A. baumannii ATCC 17978 cells were grown at 37°C with shaking (200rpm) in 35mL cultures in MH broth to OD600=0.75, at which time they were split into 15mL cultures. One 15mL sample was treated with 4µg/mL chlorhexidine (0.5x MIC), whereas the other was not treated and used as a reference. Cultures were allowed to grow for a further 30 mins (to an average final OD600= ~1.35 for untreated cells and 1.25 for chlorhexidine treated samples), when cells were harvested by centrifugation and immediately suspended in Trizol reagent (Invitrogen). Total RNA was extracted using the PureLinkTM Micro-to-Midi Total RNA Purification kit (Invitrogen), incorporating an on-column DNAseI (Invitrogen) digestion. Overall design: The experiment included using four grids of a custom Agilent 8 x 15000 spot microarray. Three biological replicates and one flip dye experiment.