Escherichia coli cells: sorted vs. non-sorted

Transcription profile of sorted Escherichia coli cells was compared to that of non-sorted cells to evaluate the effect of sorting process on transcriptome of E. coli. E. coli cells were harvest from planktonic cultures in annular reactor and stored in RNAlater. Sorting includes 2-min homogenization with OMNI TH homogenizer on ice for E. coli cells pre-stored in RNAlater and then resuspended in nuclease free phosphate buffered saline for sorting with one-step immuno-magnetic separation with anti-E. coli antibody and microbeads on a MACS separator (Miltenyi, Auburn, CA). Two condition experiments: sorted vs non-sorted. Two biological replicates with individually grown and harvested E. coli cells. Each biological replicate has two technical replicates of labeling and hybridization on microarray slides. Each slide has three built-in replicates for each probe.