Calmodulin-Tagged Phage and Two-Filter Sandwich Assays for the Identification of Enzymatic Activities

Directed evolution has proven to be a powerful route to enhance the stability, catalytic efficiency, or substrate specificity of enzymes. Large repertoires of enzyme mutants are generated, followed by the isolation of those enzyme variants with the desired catalytic properties. In this chapter, we outline two general methods for the efficient isolation of enzymatic activities from very large repertoires of protein variants.