Identification of a nisI promoter within the nisABCTIP operon that may enable establishment of nisin immunity prior to induction of the operon via signal transduction.

ABSTRACT: Certain strains of Lactococcus lactis produce the broad-spectrum bacteriocin nisin, which belongs to the lantibiotic class of antimicrobial peptides. The genes encoding nisin are organized in three contiguous operons: nisABTCIP, encoding production and immunity (nisI); nisRK, encoding regulation; and nisFEG, also involved in immunity. Transcription of nisABTCIP and nisFEG requires autoinduction by external nisin via signal transducing by NisRK. This organization poses the intriguing question of how sufficient immunity (NisI) can be expressed when the nisin cluster enters a new cell, before it encounters external nisin. In this study, Northern analysis in both Lactococcus and Enterococcus backgrounds revealed that nisI mRNA was present under conditions when no nisA transcription was occurri

SUBMITTER: Li H 

PROVIDER: S-EPMC1698219 | biostudies-literature | 2006 Dec

REPOSITORIES: biostudies-literature