Cellular Logic with Orthogonal Ribosomes

Mrc Harwell, Oxford, England, United Kingdom
Journal of the American Chemical Society (Impact Factor: 12.11). 01/2006; 127(50):17584-5. DOI: 10.1021/ja055338d
Source: PubMed


The creation and use of unnatural molecules to control cellular function is a long standing goal of the chemical community, but in general, these efforts have been directed at finding molecules to inhibit or activate a particular molecular target or function, or to elicit a particular phenotype. Here we show that multiple unnatural molecules (orthogonal ribosomes) can be used combinatorially, in a single cell, to program Boolean logic functions. These experiments show how attention to the molecular specificity of noncovalent interactions between unnatural macromolecules allows the synthesis of complex function from the "bottom-up" in living matter.

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    • "Orthogonal ribosomes: Multiple unnatural (orthogonal - O) ribosomes can be used combinatorially, in a single cell, to program Boolean logic functions [94]. O-ribosomes functioned as input, O-mRNAs as logic gate and fluorescence as output. "
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    • "However, because orthogonal ribosomes (O-ribosomes) are not constrained by any requirement to translate the proteome, they can be extensively mutated to alter and explore their properties. This property has been used to perform large-scale mutagenesis of the rRNA residues that make up the interface between large and small ribosomal subunits [40] and also to build synthetic gene regulatory circuits controlled at the level of translation [41] [42] [43]. "
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    • "An advantage of T7 polymerase is that its promoters are tightly inactive in the absence of the polymerase, thus reducing the load on the cell when uninduced (20,22). Recent advances in manipulating and minimizing the ribosome and altering the 16S rRNA to bind to alternative Shine-Delgarno sites are important steps towards the ultimate goal of simultaneous orthogonal translation (23,24). "
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