Part:BBa_B0033

RBS.4 (weaker) -- derivative of BBa_0030

Weaker RBS based on Ron Weiss thesis. Strengths relative to BBa_B0030, BBa_B0031, BBa_B0032.

Improvement

Group:iGEM2019_JiangnanU_China</br>

This year, we improved the sequence of the RBS BBa_B0033, and got the RBS BBa_K3137001.

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 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

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  COMPATIBLE WITH RFC[12]
• 21
  COMPATIBLE WITH RFC[21]
• 23
  COMPATIBLE WITH RFC[23]
• 25
  COMPATIBLE WITH RFC[25]
• 1000
  COMPATIBLE WITH RFC[1000]

Functional Parameters

biology	-NA-
efficiency	0.01

(Relative to BBa_B0034)

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Team Warsaw 2010's measurement

RBS strength (relative to B0034): 0,35%