In this dispensation of the fourth industrial revolution, protein engineering has become a popular approach for increasing enzymatic activity, stability, and titer in the biosynthesis of natural products. This is attributed to its numerous advantages (over direct isolation from plants or via chemical synthesis), including decreasing or eliminating reaction byproducts, high precision, moderate handling of intricate and chemically unstable chemicals, overall reusability, and cost efficiency. Recently, protein engineering tools have advanced to redesign and enhance natural product biosynthesis. These methods include direct evolution, substrate engineering, medium engineering, enzyme engineering and immobilization, structure-assisted protein engineering, and advanced computational. Recent successes in implementing these emerging protein engineering technologies were critically discussed in this article. Also, the advantages, limitations, and applications in industrial and medical biotechnology were discussed. Last, future research directions and potential were also highlighted.
Graphical Abstract: Plants are an excellent reservoir of enzymes with compound production applications. However, they can have several production restrictions like low enzyme activity, narrow substrate range, poor stability and loss of function in heterologous hosts. Extracting new enzymes is a popular approach against these restrictions. Nevertheless, this approach involves highly time-consuming and labor-intensive. In this article, we are exploring the protein engineering approach against these restrictions.