pkscontaining

PKS-containing refers to organisms, genomes, or gene clusters that encode polyketide synthases (PKS). Polyketide synthases are large, multifunctional enzymes that assemble polyketides, a broad and structurally diverse class of natural products with wide-ranging biological activities. PKS-containing clusters underlie the biosynthesis of many medically important compounds, including antibiotics, immunosuppressants, anticancer agents, and antifungals, as well as pigments and signaling molecules.

Polyketide synthases are typically organized into three major classes: Type I modular PKS, Type II iterative PKS, and Type III PKS. Type I modular PKS consist of multiple modules, each generally responsible for one round of chain elongation and modification. Type II PKS employ iterative enzymes that reuse catalytic domains to build aromatic polyketides. Type III PKS are smaller, often homodimeric enzymes that performIterative condensations with simple starter and extender units. PKS enzymes use acyl-CoA starter units and extender units, and carry auxiliary domains for processing steps such as ketoreduction, dehydration, and enoyl reduction. In many organisms, PKS genes appear within larger biosynthetic gene clusters that also encode tailoring enzymes, transporters, and regulatory proteins; hybrid clusters that combine PKS with nonribosomal peptide synthetase (NRPS) modules are common.

Identification and study of PKS-containing clusters rely on genome mining and bioinformatic tools such as antiSMASH and related platforms, complemented by biochemical and genetic approaches to determine product structures and biosynthetic logic. Understanding PKS-containing systems supports natural product discovery and enables metabolic engineering to produce valuable polyketides.

See also: polyketide synthase, natural product biosynthesis, genome mining, hybrid PKS-NRPS.