biostudies-literatureO'Reilly CScience Foundation Ireland7899https://www.ebi.ac.uk/biostudies/studies/S-EPMC10188554biostudies-literatureUnknown13(1)Nisin is a broad spectrum bacteriocin used extensively as a food preservative that was identified in Lactococcus lactis nearly a century ago. We show that orally-ingested nisin survives transit through the porcine gastrointestinal tract intact (as evidenced by activity and molecular weight determination) where it impacts both the composition and functioning of the microbiota. Specifically, nisin treatment caused a reversible decrease in Gram positive bacteria, resulting in a reshaping of the Firmicutes and a corresponding relative increase in Gram negative Proteobacteria. These changes were mirrored by the modification in relative abundance of pathways involved in acetate, butyrate (decreased) and propionate (increased) synthesis which correlated with overall reductions in short chain fattScientific reportsModulation of the gut microbiome with nisin.PMC10188554SFI/12/RC/2273O'Reilly CRea MCStanton CPeterson VLLawlor PGCotter PDHill CRoss RPMathur HCoakley MO'Connor PMGrimaud GMO'Donovan CMfalseModulation of the gut microbiome with nisin.Nisin is a broad spectrum bacteriocin used extensively as a food preservative that was identified in Lactococcus lactis nearly a century ago. We show that orally-ingested nisin survives transit through the porcine gastrointestinal tract intact (as evidenced by activity and molecular weight determination) where it impacts both the composition and functioning of the microbiota. Specifically, nisin treatment caused a reversible decrease in Gram positive bacteria, resulting in a reshaping of the Firmicutes and a corresponding relative increase in Gram negative Proteobacteria. These changes were mirrored by the modification in relative abundance of pathways involved in acetate, butyrate (decreased) and propionate (increased) synthesis which correlated with overall reductions in short chain fatt2023-01-01T00:00:00Z2023 May2025-04-21T22:45:22.05Z2025-04-05T18:54:25.04ZS-EPMC101885543719371510.1038/s41598-023-34586-x