SYNTHETIC BIOLOGY, PROTEIN SYNTHESIS AND DRUG DISCOVERY:
Synthetic biology is a new field that may be defined as the complex engineering of replicating systems
(http://syntheticbiology.org/). Protein synthesis is central to this field and also to antibiotic development. Important questions remain unanswered. For example,
1. What are the mechanisms of substrate recognition and peptide bond formation?
2. Can cell-free protein production be improved to rival inherently less-flexible in vivo systems?
3. What genes are required to completely reconstitute translation (the "translatome")?
4. Can new protein synthesis inhibitors be developed to combat rising bacterial resistance?
Ironically, in addition to being a target for antibiotic development, we envisioned that the translation apparatus could also be engineered to generate drug leads against translation or any other target molecules.
WHERE WE ARE:
We've reconstituted a simplified, purified translation system that has enabled:
1. Modular alteration of aminoacyl-tRNA substrates using chemical synthesis to reveal key elements for substrate function in translation,
2. Overturning of dogma on the rate-limiting step in translation,
3. Explaining why the genetic code evolved to contain proline,
4. Creation of rudimentary genetic codes de novo, and
5. Genetic screening of a model library of polypeptides in a purified system, termed "pure translation display."
We also proposed a list of genes essential for reconstitution of translation (a "minimal translatome") and developed a strategy for synthesizing and testing the genes using "BioBricks."
WHERE WE'RE GOING:
We aim to exploit our purified translation system to:
1. Determine the rules of substrate recognition by the translation apparatus,
2. Enable ligand discovery using pure translation display of peptides containing multiple, protease-resistant, unnatural amino acids,
3. Synthesize active 23 rRNA in vitro using rRNA modification enzymes associated with antibiotic resistance,
4. Optimize in vitro translation systems,
5. Determine the genes necessary for reconstitution of translation, and
6. Synthesize a life-like replicating system (a minimal cell project) dependent only on small molecules for food.