[1] Thus, CFPS enables direct access and control of the translation environment which is advantageous for a number of applications including co-translational solubilisation of membrane proteins, optimisation of protein production, incorporation of non-natural amino acids, selective and site-specific labelling.
[2][3] Due to the open nature of the system, different expression conditions such as pH, redox potentials, temperatures, and chaperones can be screened.
Common components of a cell-free reaction include a cell extract, an energy source, a supply of amino acids, cofactors such as magnesium, and the DNA with the desired genes.
The remains are the necessary cell machinery including ribosomes, aminoacyl-tRNA synthetases, translation initiation and elongation factors, nucleases, etc.
LETs can be made much more effectively via PCR, which replicates DNA much faster than raising cells in an incubator.
Usually, a separate mixture containing the needed energy source, along with a supply of amino acids, is added to the extract for the reaction.
[9][1] A major application of CFPS is incorporation of unnatural amino acids into protein structures (see expanded genetic code).
Synthetic biology has many other uses and is a bright future in fields such as protein evolution, nanomachines, nucleic acid circuits, and synthesis of virus-like particles for vaccines and drug therapy.
However, high yield production can limit the complexity of the synthesized protein, particularly in post-translational modification.
Cell-free protein synthesis has been used for over 60 years, and notably, the first elucidation of a codon was done by Marshall Nirenberg and Heinrich J. Matthaei in 1961 at the National Institutes of Health.
[1][16] They used a cell-free system to translate a poly-uracil RNA sequence (or UUUUU... in biochemical terms) and discovered that the polypeptide they had synthesized consisted of only the amino acid phenylalanine.