Evolution for the Design of Macromolecular Bioassay Reagents

Directed Evolution for the Design of Macromolecular Bioassay Reagents 

Natural biological evolution occurs as a result of naturally occurring mutations, fragmentation and loss of DNA, duplication, and other genetic processes. Furthermore, sexual recombination increases the possibility of successful genetic combinations. The selection of improved variants occurs as a result of environmental conditions or selection pressures. 

Natural proteins are adapted or optimized for function in specific physicochemical conditions. For example, enzymes isolated from bacteria found in Antarctic seawater have high activity at low temperature, but they are denatured at relatively low temperature. Thermophilic bacteria adapted to survive on hotspring water or in volcanic lakes harbor thermostable enzymes possessing almost no activity at low 

Bianalytical Chemistry, by Susan R. Mikkelsen and Eduardo Coiton ISBN 0-471-54447-7 Copyright 2004 John Wiley Sons, Inc. 

Goals for enzymatic targets of directed protein evolution have been to increase stability to denaturing agents (temperature, pH, organic solvents), improve solubility in water-organic solvent mixtures, and increase activity and/or affinity for substrate. More ambitious projects have also been undertaken to design enzymes with catalytic activity for new (but usually related) substrates. 

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