Difference between revisions of "Part:BBa K1351016"

Revision as of 18:46, 17 October 2014

comDE Quorum Sensing two component system (Freiburg Standard)

Quorum sensing two component system (histidine kinase comD, response regulator comE) of Streptococcus pneumoniae (R6) able to sense the competence stimulating peptide CSP.

CSP, a 17 amino acids long peptide pheromone, binds to and consequently activates the membrane-embedded sensor kinase ComD by changing the conformation of the polytopic kinase. ComD autophosphorylates and subsequently transphosphorylates the cognate response regulator ComE. ComE acts as transcription activator via binding to -10 promoters regions of early and late competence genes. These ComE binding sites (CEbs) consist of a 9 bp direct repeat separated by a stretch of 12 nucleotides [http://www.ncbi.nlm.nih.gov/pubmed/23216914 (Martin et al. 2013)]. BBa_K1351024, BBa_K1351025 are BioBricks containing CEbs form different promoters of S. pneumoniae.

ComE dependent promoters containing bases matching (blue) and differing (red) from the CEbs consensus sequence. (figure modified from [http://www.ncbi.nlm.nih.gov/pubmed/23216914 Martin et al. 2013)]

This part contains optimized RBS for Bacillus subtilis (in contrast to BBa_K1351015 were the native RBS was maintained) and was generated in a modified version of RFC25, where a strong Shine Dalgarno Sequence (SD) is included, and has the following prefix and suffix:

Sites of restriction enzymes generating compatible overhangs have the same color:

EcoRI and PstI in blue, NotI in green, XbaI and SpeI in red, NgoMIV and AgeI in orange. Shine-Dalgarno sequence and stop codons are underlined.

Sequence and Features