Protein Engineering: Principles, Strategies and Applications in Biotechnology

Abstract

Protein engineering is a rapidly developing field of biotechnology that involves the modification or redesign of proteins to obtain improved, altered, or novel properties. The ability to engineer proteins has significantly expanded their applications in industrial biotechnology, medicine, agriculture, food technology, environmental biotechnology, and synthetic biology. Protein engineering approaches can broadly be classified into rational design, directed evolution, and semi-rational approaches. Rational design utilises knowledge of protein structure, sequence, function, and molecular interactions to introduce specific modifications, whereas directed evolution employs iterative cycles of genetic diversification and screening or selection to identify proteins with desirable characteristics. Semi-rational strategies combine structural and computational information with directed mutagenesis to reduce the experimental screening requirements. Recent advances in structural biology, bioinformatics, artificial intelligence, machine learning, and high-throughput screening have further enhanced the efficiency and precision of protein engineering. Engineered proteins and enzymes are increasingly being developed with improved catalytic activity, thermal and pH stability, substrate specificity, solubility, resistance to inhibitors, and altered binding properties. These developments have enabled the production of optimised industrial enzymes, therapeutic proteins, vaccines, biosensors, biomaterials, and biocatalysts. Despite these advances, challenges, including protein folding, epistasis, limited sequence–function understanding, experimental screening costs, and prediction accuracy, remain important barriers. This review discusses the fundamental principles of protein engineering, major engineering strategies, emerging computational and artificial intelligence-based approaches, and their applications across biotechnology. It also highlights current challenges and future perspectives, emphasising the potential of integrated experimental and computational approaches to accelerate the design of next-generation proteins for sustainable and advanced biotechnological applications.