Nonribosomaaliset

Nonribosomaaliset, known in English as non‑ribosomal peptides (NRPs), are a diverse class of small protein-like molecules produced by many bacteria, fungi and some plant species. Unlike ribosomal peptides that are assembled by ribosomes using messenger RNA templates, NRPs are synthesized independently of the ribosome by large multi‑enzyme complexes called non‑ribosomal peptide synthetases (NRPSs). These enzymatic assemblies function modularly, with each module typically responsible for adding a specific amino acid or unusual residue to the growing chain. The modules often contain domains for activation, adenylation, thiolation, condensation and sometimes epimerization or oxidation, allowing the incorporation of non‑proteinogenic amino acids, D‑configuration residues, and various heterocyclic structures.

Because NRPSs are not constrained by genetic templates, they can generate a vast array of chemically diverse structures, including cyclic, linear or macrocyclic peptides with unusual post‑synthetic modifications. This chemical versatility underlies many important biological activities, such as antimicrobial, antifungal, anticoagulant, and enzyme‑inhibitory properties, making NRPs a valuable source in drug discovery. Notable examples include the macrolide antibiotic erythromycin, the antifungal peptide gramicidin, and the immunosuppressant cyclosporine.

In microbial ecology, NRPs often serve as signaling molecules, siderophores or anti‑competitor agents, contributing to the organism’s adaptability. The study of NRPS gene clusters, facilitated by genomic sequencing and bioinformatics, enables the prediction of novel NRPs and guides engineered biosynthesis. Overall, nonribosomaaliset represent a unique and highly productive subset of natural products with significant biomedical and industrial relevance.