Protein Engineering as a Tool for the Development of Novel Bioproduction Systems

Protein engineering is the most important tool to overcome the limitations of natural enzymes to facilitate their efficient use in biocatalysis, but also in biotransformations using engineered whole cell systems. In the past decade numerous novel concepts have been developed to create mutant libraries more efficiently, taking advantage of improved molecular biology methods and better expression systems for the target proteins. Most important are sophisticated designs of mutant libraries guided by bioinformatic tools. These achievements were complemented with the development of advanced high-throughput screening or selection methods using, for instance, fluorescence-activated cell sorting (FACS) or microfluidic systems. The latter are prime examples useful to establish novel bioproduction systems as cell-free protein biosynthesis allows protein expression and subsequent sorting of desired enzyme variants with these methods.