Team:Hamburg/Basic Part

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Basic Part

The Best Basic Part

The Gate

As a gate we used a toehold switch system which modulates a secondary structure in its mRNA that hides the ribosome binding site and the start codon of the gene that should be introduced in bacteria. Due to formation of a hairpin translation cannot be initiated. In figure 1B) the hairpin structure of the gates mRNA is shown.

We used this gate to regulate translation of a chloramphenicol resistance. The advantage is that it can be used to regulate translation of any gene of interest when it is put in front. Figure 1A) shows a scheme of the trigger complex. The affinity between the trigger complex and the gate is greater than that of the gate to itself (in the hairpin). A single trigger cannot open the gate because it contains only half the required complementary sequence.

Figure 1: A) Formation of trigger complex after translation. B) mRNA of gate sequence forms secondary structures that hide the ribosome binding site and start codon.

Figure 2: Opening of the gate due to annealing of trigger complex to gate.To use this system in bacteria we implemented the gate sequence together with a gene for chloramphenicol (BBa_K2970011), flanked by a constitutive promoter (BBa_J23100) and a strong terminator (BBa_B1002) into pSB1A3 where the ampicillin resistance can be cut out.

All basic parts

Part	Part Name/Link to registry	Part Type	Components	Length (bp)
Trigger 1	BBa_K2970000	basic part	trigger 1	68
Trigger 2	BBa_K2970001	basic part	trigger 2	68
Gate	BBa_K2970002	basic part	gate	111
Chloramphenicol resistance gene without BsmBI site	BBa_K2970011	basic part	CmR(mut)	660