Team:Bielefeld-CeBiTec

iGEM Bielefeld-CeBiTec 2017

Expanding the Genetic Code

We are exploring the application of unnatural base pairs as an expansion of the genetic code. To prevent loss of unnatural base pairs during replication, we will utilize several systems including CRISPR/Cas9. The expanded genetic code allows for the ribosomal incorporation of multiple non-canonical amino acids (ncAAs) into peptides. With their broad chemical and functional diversity, ncAAs provide a variety of promising applications including protein labeling, photocaging, structure analysis, and specific protein interactions. Therefore, our innovative toolkit for the translational incorporation of ncAAs in E. coli is a valuable contribution to iGEM. Directed evolution of tRNA/aminoacyl-tRNA synthetase pairs enables the site-specific incorporation of ncAAs into peptides. This approach results in an optimal orthogonality to the autologous translation apparatus and a high flexibility concerning the incorporation of multiple ncAAs. As proof of concept, we are developing a rapid test for prions and a new chromatography method for mild protein elution.
For more information visit our project poster on reasearch gate

Achievements


Establishment of two orthogonal methods for the detection of unnatural base pairs in a target sequence via Oxford Nanopore sequencing and an enzyme based detection method



Development of a software suite for these orthogonal methods


Integration and characterization of the nucleotide transporter PtNTT2 from P.tricornutum in E.coli for the uptake of unnatural nucleoside triphosphates



Construction of a toolbox consisting of five aminoacyl-tRNA synthetases for incorporation of non-canonical amino acids


Design, chemical synthesis and proof of functionality of a novel, fully synthetic amino acid based on cyanonitrobenzothiazol and asparagine



Modeling more than ten new aaRS sequences



Library development with several hundred thousand sequences for selecting aminoacyl-tRNA synthetases


Construction of positive and negative selection plasmids for the evolution of new synthetases for non-canonical amino acids



Improvement of an aminoacyl-tRNA synthetase test-system by introducing a FRET-system and development of a ranking system



Construction of an LED panel for irradiating 96-well microtiter plates, which can be used to manipulate non-canonical amino acids and much more



Development of an Android App to control the LED panel with your smartphone via Bluetooth


Writing a biosafety report titled “Auxotrophy to Xeno-DNA: A Comprehensive Exploration of Combinatorial Mechanisms for a High-Fidelity Biosafety System”



Writing the ChImp Report on “Chances and Implications of an Expanded Genetic Code”