Coding

Part:BBa_M36888:Design

Designed by: Shamik Mascharak, Justo Caballero and Sibel Sayiner   Group: Stanford BIOE44 - S11   (2012-12-05)

Sequence for sigma 32 transcription factor


Assembly Compatibility:
  • 10
    INCOMPATIBLE WITH RFC[10]
    Illegal PstI site found at 601
  • 12
    INCOMPATIBLE WITH RFC[12]
    Illegal PstI site found at 601
  • 21
    COMPATIBLE WITH RFC[21]
  • 23
    INCOMPATIBLE WITH RFC[23]
    Illegal PstI site found at 601
  • 25
    INCOMPATIBLE WITH RFC[25]
    Illegal PstI site found at 601
  • 1000
    INCOMPATIBLE WITH RFC[1000]
    Illegal BsaI site found at 303
    Illegal SapI.rc site found at 652


Design Notes

Anyone incorporating this part into a feedback amplification loop must beware of likely rpoH-deletion mutants. This is due to overproduction of sigma 32 under leaky promoters such as htpG (BBa_J45405). Less deletion mutants in E. coli are noted when plasmids containing rpoH are cloned at higher temperature.

Consider two facts before using this part. First, rpoH transcript activity is reduced under excess heat shock protein production. As such, feedback loops using rpoH should employ weaker bicistronic ribosome binding sites so as to optimize heat-shock response. You might also consider using the wild-type RBS (BBa_K1895001). Second, sigma 32 is turned over rapidly, with a half-life under 1 minute.

Source

The particular part described here is specific to the genome of W3110 strain E. coli.

http://ecoliwiki.net/colipedia/index.php/rpoH:Gene

References

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC211317/?page=5

http://www.researchgate.net/publication/20461625_The_activity_of_sigma_32_is_reduced_under_conditions_of_excess_heat_shock_protein_production_in_Escherichia_coli