Activity of cytotoxin P4 from the venom of the cobra snake Naja nigricollis on gram-positive bacteria and eukaryotic cell lines.

The cytotoxin P4 from the venom of the cobra snake Naja nigricollis was examined for activity against aerobic gram-positive and gram-negative bacteria, yeasts, fungi and eucaryotic cell lines by determination of minimal inhibitory concentrations (MIC) and IC50 values, respectively. Cytotoxin P4 exhibits antimicrobial activity against Bacillus subtilis, Micrococcus flavus and Sarcina lutea. Targets in gram-negative bacteria and fungi apparently were not reached. Toxicity against eucaryotic cells is in a narrow range between lethal and tolerable concentrations.