Expression OptimizationDNA2.0 employs molecular biologists and bioinformatics scientists who are experts in heterologous protein expression (see our peer reviewed articles on the subject listed below). To synthesize genes that maximize heterologous protein expression in any host, codon optmization can be directly integrated into our DNA-2-Go™ and DNA-2-Day™ custom gene synthesis platforms. Codon biases and heterologous expressionCodon usage is the single most important factor in prokaryotic gene expression. The frequencies with which different codons are used vary significantly between different organisms, between proteins expressed at high or low levels within the same organism, and sometimes even within the same operon. The most likely reason for this variation is that preferred codons correlate with the abundance of cognate tRNAs available within the cell. It is possible that codon usage and tRNA isoacceptor concentrations have coevolved, and that the selection pressure for this coevolution is more pronounced for highly expressed genes than genes expressed at low levels.
Because a synthetic gene is designed from the ground up, the codons used to encode different amino acids can be chosen to suit the expression host. We have seen numerous examples where codon optimization dramatically increases protein expression. To reduce heterologous expression problems it is important to: - Eliminate codons that are used infrequently by the desired host organism.
- Incorporate codons at approximately the frequencies found in the host's natural genes.
- Eliminate noncanonical codons.
Gene Designer software uses probabilistic design strategiesBy using codons at the frequency that they appear in the desired host organism, sufficient flexibility can be incorporated into the gene design process that expression optimization may be integrated with other design requirements. Our Gene Designer software accomplishes this by using probabilistic design based on codon usage tables where each codon is given a probability score based on the frequency distribution of the codons of the genome normalized for every amino acid. For further information: Try our free Gene Designer software, a universal software tool for all your gene design needs. |
