Part:BBa_K3171171

Vibrio natriegens native P1 promoter

V. natriegens has been reported to have a remarkable doubling time of 9.8 min. As is the case for the better-studied but slower-growing E. coli, V. natriegens increases its number of ribosomes with the growth rate in order to achieve its extraordinarily high rate of protein synthesis. Multiple mechanisms contribute to this high ribosome synthesis efficiency, including high rRNA gene copy number; strong promoters that contain near-consensus −10, −35, and UP elements; and activation by the transcription factor Fis. In addition, V. natriegens rRNA promoters exhibit the relatively short-lived open-complex characteristic of rRNA promoters in E. coli, potentially contributing to the regulation of these promoters in vivo. The native promoter P1 is constitutive.

Genes under the control of this promoter are constitutively transcribed by the organism’s ribosomal protein P1. Fluorescence measurements of the construct in E. coli and V. natriegens reveal a constitutive expression of the reporter mCherry for both organisms. Interestingly our measurements show that the expression levels in E. coli are a lot higher than in V. natriegens as the fold change is 225 for E. coli compared to 3 for V. natriegens (figure 1).

Figure 1: Fluorescence of the reporter mCherry under control of the constitutive P1 promoter in V. natriegens and E. coli in comparison to control without plasmid.