Combinatorial Evolution of Enzymes and Synthetic Pathways Using One-Step PCR

Area of Science:

• Biotechnology
• Molecular Biology
• Synthetic Biology

Background:

• DNA engineering is crucial for advancing modern biotechnology.
• Directed evolution requires efficient methods for generating diverse mutant libraries.

Purpose of the Study:

• To introduce a versatile method for rapidly creating multiple combinatorial DNA mutations.
• To demonstrate the utility of this method in enzyme and pathway engineering.

Main Methods:

• Developed a method named "rapidly efficient combinatorial oligonucleotides for directed evolution" (RECODE).
• Utilized a one-reaction system combining a thermostable high-fidelity DNA polymerase and DNA ligase.
• Applied RECODE to construct variant libraries and optimize biological systems.

Main Results:

• Successfully constructed a variant library for rpoS promoters with activity ranging from 8-460%.
• Generated a novel heparinase through directed evolution of leech hyaluronidase, introducing over 30 mutations.
• Optimized the heme biosynthetic pathway, achieving a 20-fold increase in production (2500 ± 120 mg L(-1)).

Conclusions:

• The RECODE method offers an efficient and simple approach for creating diverse mutant libraries.
• This technique significantly enhances the rapid evolution and optimization of enzymes and synthetic pathways.
• RECODE empowers researchers with unprecedented capabilities in DNA engineering for biotechnology applications.