Transcriptional analysis of Escherichia coli O157:H7 delta yedL in MEM-HEPES

Deletion of yedL was found to signifcantly decrease type three secretion in EHEC O157:H7. Transcriptional profiles of Escherichia coli O157: H7 and the isogenic yedL mutant were generated and compared. RNA was extracted from biological tripicate flasks and labelled with Cy3 or Cy5. Reference RNAs (w.t. TUV93-0) were pooled and divided into 80pmol aliquots for hybridisation. 80pmol of test Cy3 labelled cDNA was mixed with 80 pmol of pooled reference Cy5 labelled cDNA and hybrised to a single micorarray. Triplicate microarrays were scanned and data analysed using Genespring GX 7.3