RBS.4 (weaker) -- derivative of BBa_0030
As we all know, RBS refers to a sputum-rich untranslated region upstream of the initiation codon AUG. BBa_B0033 is a weaker RBS based on Ron Weiss thesis. Compared with BBa_B0030, BBa_B0031, BBa_B0032, BBa_B0034, BBa_B0033 is the weakest, and whose RBS strength is 0.35% of BBa_B0034. By analyzing their sequence, we found that BBa_B0033 has fewer purines and no not have AAA sequence. SO we designed the RBS by adjusting the proportion of bases.
Then we ligated the two RBS with promotor rsmH (BBa_K3137000) and gene gfp (BBa_K3137011) and transform into E. coli BL21 to compare their green fluorescence. And take E. coli BL21 as a control. The figure below shows that BBa_K3137001 has the stronger fluorescently protein expression than BBa_B0033, that means it’s efficient to increase the protein expression by increasing the number of purines in the RBS sequence, which is beneficial to the binding of ribosomes.
Sequence and Features
- 10COMPATIBLE WITH RFC
- 12COMPATIBLE WITH RFC
- 21COMPATIBLE WITH RFC
- 23COMPATIBLE WITH RFC
- 25COMPATIBLE WITH RFC
- 1000COMPATIBLE WITH RFC
(Relative to BBa_B0034)
Functional Parameters: Austin_UTexas
Burden Imposed by this Part:
Burden is the percent reduction in the growth rate of E. coli cells transformed with a plasmid containing this BioBrick (± values are 95% confidence limits). This BioBrick did not exhibit a burden that was significantly greater than zero (i.e., it appears to have little to no impact on growth). Therefore, users can depend on this part to remain stable for many bacterial cell divisions and in large culture volumes. Refer to any one of the BBa_K3174002 - BBa_K3174007 pages for more information on the methods, an explanation of the sources of burden, and other conclusions from a large-scale measurement project conducted by the 2019 Austin_UTexas team.
This functional parameter was added by the 2020 Austin_UTexas team.