Characterisation of antibacterial activity of peptide isolated from the venom of the spider Cupiennius salei (Araneae : Ctenidae)

The characterisation of the antimicrobial activity of five antibacterial pe ptides, isolated from the venom of the neotropical wandering spider Cupienn ius salei is reported here. The peptides have a molecular mass, determined by electrospray ionisation-mass spectrometry, between 3-4 kDa, Minimal inhi bitory concentrations against five different bacteria species were determin ed by a liquid growth inhibition assay. All five peptides showed minimal in hibitory concentrations that are comparable to those of other known antibac terial peptides, like insect defensins and cecropins, found in the last yea rs in a large diversity of animals. The peptides are supposed to lyse the c ells by formation of either distinct channels or pores, but their mode of a ction is not yet revealed. (C) 1999 Elsevier Science Ltd. All rights reserv ed.