In vitro activities of tachyplesin III against Pseudomonas aeruginosa.
The in vitro activities of tachyplesin III were investigated against 20 multidrug-resistant Pseudomonas aeruginosa clinical isolates. Methods included minimal inhibitory concentrations, minimal bactericidal concentrations, time-kill studies, checkerboard titration method, endotoxin-binding activity and cytotoxicity assay. Overall the organisms were susceptible to the peptide at concentrations of 0.50-4 mg/l. Tachyplesin III completely inhibits the endotoxin procoagulant activity at 22.36 mg/l concentration. Fractional inhibitory concentration indexes demonstrated synergy between the peptide and betalactams or colistin. In conclusion, the intrinsic antibacterial and antiendotoxin activities and the synergistic interactions demonstrated with clinically used antibiotics make tachyplesin III valuable as potential candidate for new therapeutic strategies aimed to treat P. aeruginosa infection.
Cirioni
Oscar
O
Institute of Infectious Diseases and Public Health, Università Politecnica delle Marche, Ancona, Italy.
Giacometti
Andrea
A
Kamysz
Wojciech
W
Silvestri
Carmela
C
Riva
Alessandra
A
Della Vittoria
Agnese
A
Abbruzzetti
Alessandra
A
Lukasiak
Jerzy
J
Scalise
Giorgio
G
D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000494:pharmacology; D023181:Antimicrobial Cationic Peptides / Q000138:chemical synthesis / Q000494:pharmacology*; D002442:Ceftazidime / Q000494:pharmacology; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D002939:Ciprofloxacin / Q000494:pharmacology; D004268:DNA-Binding Proteins / Q000138:chemical synthesis / Q000494:pharmacology*; D024901:Drug Resistance, Multiple, Bacterial; D004357:Drug Synergism; D006801:Humans; D008826:Microbial Sensitivity Tests; D050296:Microbial Viability / Q000187:drug effects; D010456:Peptides, Cyclic / Q000138:chemical synthesis / Q000494:pharmacology*; D011550:Pseudomonas aeruginosa / Q000187:drug effects*
D000900:Anti-Bacterial Agents; D023181:Antimicrobial Cationic Peptides; D004268:DNA-Binding Proteins; D010456:Peptides, Cyclic; C057636:tachyplesin peptide, Tachypleus tridentatus; D002939:Ciprofloxacin; D002442:Ceftazidime