The nisin O cluster: species dissemination, candidate leader peptide proteases and the role of regulatory systems

Nisin O is an antimicrobial peptide encoded by the human gut bacterium Blautia obeum A2-162 which has antimicrobial activity against clinically relevant organisms. The nisin O biosynthetic gene cluster (BGC) varies from other nisin BGCs as it lacks a leader-peptide cleaving protease and contains two bacterial two-component response regulator-histidine kinase (RK) systems. The dissemination of the nisin O cluster, the final proteolytic biosynthesis step and the regulation of nisin O are …