Figure 3 - Combinatorial assembly of PKS modules through synthetic biology.

Building blocks comprising loading module (LM^ery), intrapeptide linker (LI), N-terminal interpeptide linker (LN), synthetic donor and acceptor (extender) modules, C-terminal interpeptide linker (LC) and thioesterase (TE^ery). The LM and TE are derived from the erythromycin PKS (ery). The restriction sites allowing their ready assembly are annotated. All of the genes are introduced into the E. coli expression host on separate and compatible plasmids, and typical examples of a final protein arrangement and chemical (triketide lactone, TKL) product are shown below. AT, acyltransferase; ACP, acyl carrier protein; KS, -ketoacylsynthase; KR, -ketoacylreductase. Modified with permission from ref. 29.