HIGH-SENSITIVITY OF MYCOBACTERIUM SPECIES TO THE BACTERICIDAL ACTIVITY BY POLYLYSINE

Bactericidal effects of polylysine on different bacterial species were measured. Marked differences in sensitivity were observed. Based on the concentration of polylysine required to reduce cell viability by 50%, Mycobacterium smegmatis and Mycobacterium tuberculosis were found to be the most sensitive and Escherichia coli the most resistant. In two Gram-positive organisms, Staphylococcus epidermidis and Streptococcus salivarius exhibited significant differences in sensitivity which suggests that the relationship between sensitivity towards polylysine and bacterial cell type is not necessarily a function of the overall cell envelope structure. The high sensitivity of mycobacteria suggests the possible use of polylysine, or a conjugate of polylysine and another agent in anti-mycobacterial drug design.