BLAST analysis of the iclR promoter. Basic Local Alignment Search of the promoter region of iclR in an E. coli K12 MG1655 and BL21 reveals 2 mutations (highlighted by boxes) in the BL21 strain. The binding sites of the regulators FadR and IclR (autoregulator) are underlined. TS stands for transcription start. Results were obtained using the NCBI online tool http://blast.ncbi.nlm.nih.gov.