Recent studies on the mode of action have revealed exciting features of multiple 
activities of nisin and related lantibiotics making these peptides interesting 
model systems for the design of new antibiotics (Molec. Microbiol. 30 (1998) 
317; Science 286 (1999) 2361; J. Biol. Chem. 276 (2001) 1772.). In contrast to 
other groups of antibiotic peptides, the lantibiotics display a substantial 
degree of specificity for particular components of bacterial membranes. 
Mersacidin and actagardine were shown to bind with high affinity to the lipid 
coupled peptidoglycan precursor, the so-called lipid II, which prevents the 
polymerisation of the cell wall monomers into a functional murein sacculus. The 
lantibiotics nisin and epidermin also bind tightly to this cell wall precursor; 
however, for these lantibiotics the binding of lipid II has two consequences. 
Like with mersacidin blocking of lipid II inhibits peptidoglycan biosynthesis; 
in addition, lipid II is used as a specific docking molecule for the formation 
of pores. This combination of lethal effects explains the potency of these 
peptides, which are active in nanomolar concentration. Other type-A lantibiotics 
are believed to also use docking molecules for pore formation, although 
identification of such membrane components has not yet been achieved.