A. James Link

Biography

Despite advances in protein pharmaceuticals, the majority of diseases are still treated with small molecule drugs. One of the difficulties in using proteins as therapeutics has been the relative difficulty of generating and screening large libraries of functional proteins. This limitation has been eased with the dawn of recombinant DNA techniques that permit the rapid generation of diversity within a gene of interest. With these ideas in mind, the goal of the Link lab is ultimately to develop proteins of medical and therapeutic importance using protein engineering techniques and high-throughput screening. The main protein engineering tool behind these experiments is directed evolution, which involves the generation of large libraries of protein mutants at the genetic level followed by screening or selection of functional variants. The directed evolution algorithm will be applied to natural proteins in order to improve specific functions, such as binding affinity or efficacy. Our high-throughput screening tool of choice is flow cytometry, which permits quantitative analysis of >108 protein variants per day. In addition to evolutionary protein engineering techniques, we will also employ non-natural amino acids in order to introduce novel chemical functionality into engineered proteins. Unnatural amino acids can install unique “bioorthogonal” chemical handles into proteins for downstream addition of small molecules or polymers which may greatly enhance the therapeutic utility of the protein. As the bacterium E. coli is the preferred host for these experiments, a significant effort in the lab will be applied toward proteomic and genomic analyses of E. coli under stresses such as recombinant protein expression or unnatural amino acid incorporation.

Research Interest

Bioengineering