Operons promoter

Translation Initiation Site. In eukaryotes, if the transcription start site is known, and there is no intron interrupting the 5 UTR, Kozak s rule (Kozak, 1996) probably will locate the correct initiation codon in most cases. Splicing is normally absent in prokaryotes, yet because of the existence of multicitronic operons, promoter location is not the key information. Rather, the key is reliable localization of the ribosome binding site. The TATA sequence about 30 bp from the transcription start site may be used as a possible resource. 

Qian, J. et al (2006) Nucleotide mutations in purA gene and pur operon promoter discovered in guanosine-and inosine-producing Bacillus subtilis strains. Biotechnol Lett., 28 (12), 937-941. 

We report here the isolation of the R. capsulatus bchCA operon oxygen-regulated promoter by in-frame fusion to a plasmid-bome lacZ gene (11), The DNA sequence of the bchCA operon transcriptional regulatory region was determined, and the 5 end of the bchCA mRNA was mapped by low resolution SI nuclease protection analysis and high resolution primer extension experiments. Sequences with similarity to the puf operon promoter (7,8) were identified immediately upstream of the bchCA mRNA 5 end. 

In Fig. 5 is shown an alignment between the DNA sequence flanking the bchCA transcript 5 end and proposed oxygen-regulated puf operon promoter sequences (7,8). Identical sequences are enclosed in boxes and consist of (i) a conserved 5 -CGGGC-3 that is located 23 nt upstream of the puf +1 site and 19 nt upstream of the major bchCA 5 end (ii) a 5-TTCA-3 located 6 nt (p /promoter) or 7 nt (putative bdhCA promoter) downstream of the 5 -CGGGC-... 

FIGURE 4. Alignment of puf operon promoter sequences with proposed promoter sequences from the bchCA operon. Numbers of the first and last nucleotides of these sequences correspond to the sequence positions given for the pu/operon promoter region (7), and of the bchCA operon promoter region (Fig. 2). Identical sequences are boxed, and the nucleotides from which transcription is proposed to be initiated are marked by arrows. 

Van Rooijen, R. J., Gasson, M. J., De Vos, W. M. (1992). Characterization of the Lactococcus lactis lactose operon promoter contribution of flanking sequences and LacR repressor to promoter activity. Journal of Bacteriology, 174, 2273-2280. 

Genetic analysis has shown that there is only one promoter and no internal termination large operon sequences have been found, indicating that this gene duster is one very large operon. 

Fig. 24.5 Insertion of a cloned insulin gene into a vector carrying a bacterial promoter. The arrow indicates the direction of transcription. If we suppose the bacterial promoter is derived from the lactose operon then transcription will be initiated only in the presence of lactose.

Inoue, C., Sugawara, K., and Kusano, T., Thiobacillus ferrooxidans mer operon Sequence analysis of the promoter and adjacent genes, Gene, 96 (1), 115-120, 1990. 

The vector is used to express the genes of the sox operon (soxA, soxB, and soxC) from the constitutive promoter and so, Rhodococcus, Gordona, and Nocardia may be transformed with this vector and used in BDS of fossil fuels. Equivalent patents GB0311395D, ITMI20021217. 

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