The typing of Morganella morgani by bacteriocin production and sensitivity

A typing scheme for Morganella morgani based on bacteriocin (morganocin) production and sensitivity is described. These characteristics were determined by testing 160 strains in all combinations and permitted their differentiation into 90 types. Morganocin production was induced with mitomycin C and morganocin sensitivity determined with a diluted inoculum on Lab-lemco agar at 30 degrees C. Most strains (82.5%) produced morganocins and 49 different types were defined. Most strains (97.5%) were sensitive to morganocins and usually to several different types. The scheme is more discriminating than other reported methods. The finding in an epidemiological survey of the carriage of certain strains in the bowel for several weeks suggests that in practice the method is stable and reproducible.