Difference between revisions of "Part:BBa K598027"

Revision as of 07:01, 5 October 2011

AND gate (BBa_K228258) regulated by theophylline riboswitch P1G1 (BBa_K598005)

This is an AND gate regulated by a theophylline riboswitch. The translational strength of T7ptag is regulated by theophylline concentration.

The AND gate we utilized was designed by Anderson and his colleagues and consequently standardly redesigned by [http://2009.igem.org/Team:PKU_Beijing/Project/AND_Gate_1/Design PKU_Beijing 09 team].

Figure 1: The construction and mechanism of AND gate. A). The standardly redesigned AND gate of PKU_Beijing 09 team. B). The topology and mechanism of AND gate. Parts showing in box constitute the core processing module. .

As shown in Fig. 1B, pBAD promoter serves as input 1. It is activated by arabinose, leading to the expression of SupD, an amber suppressor tRNA. The input 2 is pSal promoter activated by salicylate via binding to NahR. It regulates the expression of a T7 polymerase coding sequence with two amber codons reside in the position 8 and 14 (T7ptag), resulting in premature translational termination. When both T7ptag and SupD tRNA genes are expressed, functional T7 polymerase would be synthesized and consequently actives output, T7 promoter. A green fluorescent protein (GFP) generator regulated by T7 promoter serves as a reporter.

By placing a theophylline-responsive RNA controller element upstream of the coding sequence, we obtained an AND gate modulator whose T7ptag gene translation rate varies in response to ligand concentration.

Ligand responsive pattern of AND gate. .

Sequence and Features