Plug-and-play engineering of modular polyketide synthases.

Area of Science:

• Biochemistry
• Synthetic Biology
• Enzymology

Background:

• Modular polyketide synthases (PKSs) are crucial for producing complex natural products like antibiotics.
• Their modular nature offers potential for creating novel molecules via combinatorial biosynthesis.
• However, engineering hybrid PKS pathways often leads to reduced enzyme activity and lacks established design principles.

Purpose of the Study:

• To establish a general principle for PKS reprogramming.
• To enable the custom production of designer polyketides with tailored properties.
• To expand the utility of PKS engineering for creating novel molecules.

Main Methods:

• Identification and validation of two conserved motifs as robust cut sites for connecting PKS modules.
• Construction of hybrid PKS pathways using these cut sites.
• Demonstration of custom polyketide production with varied starter units, extender units, and reduction states.

Main Results:

• A widely applicable strategy for designing hybrid PKSs was developed.
• The identified cut sites successfully facilitated the connection of modules from different PKS pathways.
• Custom polyketides with diverse structural features were successfully produced.
• The strategy was extended to hybrid pathways involving cis-AT PKS, trans-AT PKS, and nonribosomal peptide synthetases.

Conclusions:

• The findings enable a plug-and-play approach for reprogramming modular PKSs.
• This strategy facilitates the application of PKS assembly lines for bioproducing designer molecules.
• The established method overcomes limitations in PKS engineering, paving the way for novel compound discovery.