BASIC PART

COMPOSITE PART

OVERVIEW

We built and submitted a series of useful composite parts this year. The following six composite parts are the most significant with great application and research value.

These six parts belong to six plasmids respectively, which are all the components of a light control system with three light control circuits, including a ‘sensor array’, a ‘circuit’, a ‘resource allocator’ and ‘actuators’.

The first one, BBa_K2598050, is our best composite part, which contains three RBSs, CGG（BBa_K2598011）, T3（BBa_K2598015） and phIF regulated by 3 promoters, PcpcG2-172, PphlF, PfixK2 respectively. The phIF is a repressor to switch off the blue-light output promoter when blue-light sensor is switched on. The CGG, in the blue-light circuit, and T3, in the green-light circuit, are both ‘sigma’ fragments that are a significant part in the resource allocator, which have the DNA-binding domain and can combine core fragment that is another necessary part produced by theresource-allocation system connecting the inputs with the outputs to form a full-functional RNA polymerase. And when σCGG combines the core fragment, they form a full-functional RNA polymerase to induce the expression of the blue-light output. Similarly, combination of σT3 and the core fragment can induce the green-light output. And these ‘sigma’ fragments are orthogonal and almost do not effect each other.

The second part, BBa_K2598049, codes three light sensors, Cph8*, CcaSR and YF1 + fixJ, which is carried on one plasmid, pJFR1(KX011464), under the promoters of J23106, J23108 and laclq35（BBa_K2598007）to sense red, green and blue light respectively. Cph8 is a chimeric histidine kinase that is switched on by infrared (705 nm) light and off by red (650 nm) light. So it can be used as a red light sensor. CcaSR is a green-light sensor based on the membrane-associated histidine kinase CcaS and its response regulator CcaR, which can be switched on by green (535 nm) light, inducing the promoter PcpcG2-172 (BBa_K592003) and off by far-red (672 nm) light. YF1 is a fusion protein of YtvA (B subtilis) and FixL (B japonicum) that can sense blue light. The fixJ is the wild-type response regulator to YF1. They can form a blue light sensor and transfer the signal to next module.

The third part, BBa_K2598051, contains CI, another repressor to switch off the red-light output promoter when red-light sensor is switched on, K1F（BBa_K2510004）, the third ‘sigma’ fragments that can combine with core fragment to induce the red-light output. And these three ‘sigma’ fragments are orthogonal and almost do not effect each other. This part is regulated by PompC1157 and Pλ promoters.

The forth part, BBa_K2598053, is the output part encoding three fluorescent proteins outputs, RFP, GFP and BFP, on one plasmid. It uses DT16（BBa_K2598031）, T7（BBa_K2598024） and DT5（BBa_K2598028） as terminators and PK1F（BBa_K2598030）, PCGG（BBa_K2598023） and PT3（BBa_K2598026） as promotors corresponding to red, green and blue light circuits respectively. Based on the forth part, the fifth part, BBa_K2598052，changes three fluorescent proteins outputs to three kinds of enzymes, including gusA（BBa_K330002）, lacZ（BBa_I732005） and bFMO（BBa_K2598027） that can combine with substrate in the medium to produce red, green and blue color.

Similarly，based on the forth part, the sixth part, BBa_K2598061, constructed by our team this year changes three fluorescent proteins outputs to three chromoproteins, including eforRed, amilGFP and aeBlue.

All composite parts are all listed in the table below.