Location of the phzM gene with its transcriptional start site and the nucleotide sequence of the phzM promoter region in Pseudomonas sp. strain M18. (A) Location of phzM with its transcriptional start site. Numbering is relative to the transcriptional start site. A putative lux-like box (black box) is located upstream of the transcription start site. The length of the space between phzM and phzA1 is 696 bp. (B) Nucleotide sequence of the phzM promoter region. In strain M18, the mRNA start site of phzM, mapped by 5′ RACE, is at position −270, which is occupied by the T nucleotide indicated by a dark gray box in bold, while in strain PAO1, it is at position −269, which is occupied by the C nucleotide in bold. The potential lux-like box is enclosed in a rectangle. The ATG translational start codon is shaded light gray.