prnC

prnC is a bacterial gene that is commonly discussed as part of the pyrrolnitrin biosynthesis gene cluster, often denoted prnABCD. Pyrrolnitrin is a secondary metabolite with antifungal activity produced by several Gram-negative bacteria, including Pseudomonas species and related genera. The prn gene cluster encodes enzymes responsible for the conversion of tryptophan into the chlorinated, nitro-containing pyrrolnitrin scaffold, enabling the organism to suppress competing fungi in its environment.

The precise enzymatic role of prnC has been investigated in various studies, but the full biochemical function can vary among strains. In many descriptions, prnC is considered to encode a protein that participates in a late step of the biosynthetic pathway, potentially acting as an oxidoreductase or another type of biocatalyst required for the formation of the final pyrrolnitrin molecule. Disruption of prnC frequently results in reduced or abolished pyrrolnitrin production, supporting its involvement in the pathway, even if the exact substrate and reaction are not universally agreed upon.

Genomic context and distribution: prnC is typically found within the prnABCD operon or gene cluster in pyrrolnitrin-producing bacteria. The cluster often resides on the chromosome and, in some species, on plasmids. The presence of prnC, along with other prn genes, correlates with the ability to synthesize pyrrolnitrin and to exhibit antifungal activity in certain ecological niches.

Applications and significance: understanding prnC and the prn operon informs studies on microbial biocontrol, natural product biosynthesis, and the regulation of secondary metabolism in bacteria.