During our project we had a great deal of work with different types of promoters - constitutive and indusible. During the planning of the project and the accumulation of knowledge about the various parts, we discovered that much information is lacking about many of these parameters, and the information that exists exists scattered among many places and is not arranged in one place. We chose two modulators - TDH3 [BBa_K124002] of team iGEM08_Brown and PGK1 [BBa_K2110012] of team iGEM16_Tianjin, two strong constitutive permutative promoters, and improved their descriptions and information about them, referring to the main sources we used. We hope that groups coming after us will have faster and more convenient access to information when they come to choose the parameters they want to use.
Improve an existing part
The miraculin glycoprotein, originally produced from the Synsepalum dulcificum plant, is a non-cariogenic substance, with a glycemic index of zero. It is suitable for consumption by diabetics and has the ability to convert sour taste into sweet taste. However, miraculin does not change the taste of the foods / drinks consumed. The mechanism of action of this special protein is still not entirely clear, but it is known that it is triggered in the presence of a low pH. Because miraculin is a glycoprotein made by plant cells, therefore a yeast like S. cerevisiae would make a better expression host than bacteria. We codon optimize the part for yeast expression. In Addtion, we added few more feature:
First, we added the ADH1 promoter at the beginning of the sequence. The ADH1 promoter is a strong constitutive promoter, that uses for protein expression in yeast. Originally the ADH1 promoter regullate the expression of the Alcohol Dehydrogenase 1 enzyme at Saccharomyces Cerevisiae. This version of the promoter is a shortened one, and it is not inhibited by ethanol. Second, we added a histidine tag for purification of the prepared protein, and finally added the ADH1 terminator for more effective expression at the end.
