ABSTRACT
Concerned with the construction and design of novel biocatalysts, the enzyme engineering served to overcome the limitations of native enzymes, in order to create biocatalysts with tailored functions, to facilitate industrial applications. The enzymes, being recognized by screening and discovery workflows and further tailored by engineering platforms, are of immense potential as improved biocatalysts. Functional metagenomics is a powerful tool to identify novel enzymes followed by the construction of metagenome-based enzyme libraries. And the subsequent screening of these enzyme libraries is in turn facilitated by ultra-high-throughput-based, for example FACS or microfluidics, enzyme engineering technologies. Relies on the compartmentalization of reaction components, in order to detect and measure assay signal within the reaction compartments, the enzyme engineering platforms are designed which include cell-as-compartment platforms, droplet-based platforms andmicro-chamber-based platforms. The metagenomics approach and high-throughput screening by these three prime enzyme engineer platforms are the focus of this review.