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bioRxiv · 10.1101/2020.09.12.294553

Some theoretical aspects of reprogramming the standard genetic code

Abstract

1Reprogramming of the standard genetic code in order to include non-canonical amino acids (ncAAs) opens a new perspective in medicine, industry and biotechnology. There are several methods of engineering the code, which allow us for storing new genetic information in DNA sequences and transmitting it into the protein world. Here, we investigate the problem of optimal genetic code extension from theoretical perspective. We assume that the new coding system should encode both canonical and new ncAAs using 64 classical codons. What is more, the extended genetic code should be robust to point nucleotide mutation and minimize the possibility of reversion from new to old information. In order to do so, we follow graph theory to study the properties of optimal codon sets, which can encode 20 canonical amino acids and stop coding signal. Finally, we describe the set of vacant codons that could be assigned to new amino acids. Moreover, we discuss the optimal number of the newly incorporated ncAAs and also the optimal size of codon blocks that are assigned to ncAAs.

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Nowak, K., Blazej, P., Wnetrzak, M., Mackiewicz, D., Mackiewicz, P.. 2020-09-13. Some theoretical aspects of reprogramming the standard genetic code. https://doi.org/10.1101/2020.09.12.294553

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