Data from: Increased survival of experimentally evolved antimicrobial peptide-resistant Staphylococcus aureus in an animal host

Antimicrobial peptides (AMPs) have been proposed as new class of
antimicrobial drugs, following the increasing prevalence of bacteria
resistant to antibiotics. Synthetic AMPs are functional analogues of
highly evolutionarily conserved immune effectors in animals and plants,
produced in response to microbial infection. Therefore, the proposed
therapeutic use of AMPs bears the risk of ‘arming the enemy’: bacteria
that evolve resistance to AMPs may be cross-resistant to immune effectors
(AMPs) in their hosts. We used a panel of populations of Staphylococcus
aureus that were experimentally selected for resistance to a suite of
individual AMPs and antibiotics to investigate the ‘arming the enemy’
hypothesis. We tested whether the selected strains showed higher survival
in an insect model (Tenebrio molitor) and cross-resistance against other
antimicrobials in vitro. A population selected for resistance to the
antimicrobial peptide iseganan showed increased in vivo survival, but was
not more virulent. We suggest that increased survival of AMP-resistant
bacteria almost certainly poses problems to immune-compromised hosts.