Genetic diversity of polyketide synthases and nonribosomal peptide synthetases in fungi

Abstract Many fungi are prolific sources of polyketides and nonribosomal peptides-derived chemically diverse secondary metabolites of pharmaceutical and biotechnological interest. Nonribosomal peptides and polyketides are synthesized by multimodular nonribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) enzymes, respectively. Many fungal genome sequence data are now publicly available that contain numerous genetic codes of previously undetected novel secondary metabolites. Novel findings have also revealed various mechanisms of NRPS and PKS evolution in different fungal taxa. These mechanisms help us to understand the different strategies employed by fungal communities to control their metabolic potential to produce diverse metabolic molecules. These metabolites, in turn, execute many prominent cellular functions such as antagonizing various invaders, controlling different cellular functions, viz., oxidative stress, cell wall development, cell surface properties, sexual and asexual reproduction, iron scavenging and sequestering, etc. Accordingly, the present review highlights and focuses on the existence of such diversified NRPS- and PKS-derived secondary metabolites and their regulatory biosynthetic gene clusters in different fungal communities.