Fig. 2.

The sequence of the promoter and 5′-UTR encoding region of the kdp operon. a Mapping of the transcription start site (TSS) of kdp operon. The 5′-rapid amplification of cDNA ends (5′-RACE) adaptor sequence (boxed in red) along with the kdp transcript sequence after DNA sequencing were shown. The TSS is shaded in yellow. b The sequence of the kdp promoter (−43 to −1) and the 5′-UTR encoding region (+1 to +370). The −35 box and −10 box, as well as the +1 position, are marked in blue, and the cyclic diadenylate monophosphate (c-di-AMP) riboswitch encoding region is underlined (+28 to +227). Among them, the aptamer encoding region is marked in red (+28 to +171), while the intrinsic terminator in the expression platform encoding region (+172 to +227) is marked in bright green. The start codon ATG of kdpF is shown in bold