Structure-activity study of the lantibiotic mutacin II from Streptococcus mutans T8 by a gene replacement strategy

Experiments were conducted to create a host-vector expression system for genetic manipulation of the lantibiotic mutacin II structural gene from Streptococcus mutans. A host strain was developed that contains all the genetic information for modification, export and processing of the mutated peptides to create an engineered mutacin. The cysteines were replaced with alanines to examine the role of the thioether bridges in the gene's antimicrobial activity.