Fig. 2

Molecular strategy for CRISPRi-based hemC repression. The four plasmids with their major genetic features, such as promoters, antibiotic resistance markers, key genes, for CRISPRi are shown. Select hemC-targeting sequences and their associated positions in the hemC gene (i.e., D1, D2, D3, D4, D5, D6, D7, D8, and D9) are shown as well. Note that the sequence location, GC content, and predicted hemC expression efficiency for various hemC-targeting sequences are shown in Additional file 1, in which select hemC-repressed strains derived from DSL∆iclR∆sdhA were characterized for quantification of the relative hemC mRNA level using qRT-PCR compared to the control DSL∆iclR∆sdhA. All qRT-PCR experiments were conducted in duplicate