• Neisseria meningitidis;
  • bacteriocin sensitivity;
  • serogroup;
  • serotype

Bacteriocin-like agents from five strains of Neisseria meningitidis were active against other meningococci and some other Neisseria species. Meningococci belonging to the same serogroup or serotype could be subdivided into distinct bacteriocin types. Insensitivity to the inhibitory agents was observed more frequently among serologically groupable strains than among non-groupable. Strains belonging to serogroup B were more often insensitive to the inhibitors released by four of the donor strains (P201, P213, P241, 99/79) than other groupable strains. Insensitivity to the bacteriocin-like activity of the fifth donor strain (77/79A) seemed to be evenly distributed among strains of different groups. Strains of serotype 15 were more often insensitive to the five inhibitors than strains belonging to other types. Group B and type 15 are most frequently observed among strains isolated from clinical cases in Norway.