earticle

영어

Previously, it was found that cloning and subsequent expression of a flavin-containing monooxygenase (FMO) gene from the Methylophaga aminisulfidivorans MPT (KCTC 12909) was responsible for producing, the blue pigment, indigo in E.coli. The cloned recombinant plasmid, designated as pBlue 1.7, contained a 1.7 kbp DNA fragment from M. aminisulfidivorans MPT genome. Sequencing of the plasmid revealed it is composed of the complete open reading frame of the fmo (1371 bp) and promoter region. In this study, the fmo promoter was analyzed to investigate its transcription regulation patterns. In the promoter region, the transcription start site (TSS) was localized 287 base pairs upstream of the transcription initiation site. In addition, the fmo promoter sequence contains the extended -10 region (TGxxTATCCA) site, sigmaS (rpoS) and CRP (c-AMP receptor protein) binding site. To verify importance of the ropS binding site for fmo transcription, the fmo gene was expressed in E. coli GN112-rpoS(-) and the transcription level was compared to E.coli DH5a-rpoS(+). This experiment showed that transcription levels of the fmo and indigo production was dramatically decreased in the E. coli GN112-rpoS(-), indicating the rpoS binding site was crucial for transcriptional regulation of fmo in E. coli cells.