Fig. 3.

A Gene arrangement in ΔmcyB (top) versus the PCC 7806 wildtype (bottom) genome. In the PCC7806 wildtype, an IS1-family transposase is inserted in the region between genes encoding a tetratricopeptide repeat protein and an efflux RND transporter. B Transcription of the genes in the order shown in Fig. 3A. In the PCC 7806 wildtype, insertion of the IS1-family transposase in the region between genes encoding a tetratricopeptide repeat protein and an efflux RND transporter leads to significantly decreased expression (p < 0.001) of the gene encoding a tetratricopeptide repeat protein and a hypothetical protein. Expression of the efflux RND transporter is significantly different between ΔmcyB and PCC 7806 wildtype at control growth temperature (26° C) (p < 0.001) but not cold (19° C). Differences in expression for the RND transporter are probably not due to the IS1-family transposase, since the two strains have similar expression profiles in the cold. Gene expression data is not shown for the ORF at the end of the RND transporter (white arrow, transcribed on opposite strand) because TPM values were < 6 for both strains and did not appear impacted by the transposase IS1-family