title: In vitro activity of PR-39, a proline-arginine-rich peptide, against susceptible and multi-drug-resistant Mycobacterium tuberculosis.
abstract: We have investigated the in vitro activity of antimicrobial peptides against Mycobacterium tuberculosis using a radiometric method and cfu determinations. PR-39, a proline-arginine-rich antibacterial peptide from porcine leucocytes, was found to be active against drug-susceptible as well as multi-drug-resistant (MDR) clinical isolates of M. tuberculosis. The activity of PR-39 was concentration dependent, with 80% growth inhibition of M. tuberculosis H37Rv at 50 mg/L. The MDR M. tuberculosis strains E1380/94 and P34/95 were less susceptible to PR-39, with 39 and 49% growth inhibition at 50 mg/L peptide, respectively, suggesting a lower susceptibility than strain H37Rv and drug-susceptible clinical isolates. Reduction of counts of M. tuberculosis H37Rv and the MDR M. tuberculosis strain E1380/94 by PR-39 indicated that the growth inhibition seen in the radiometric assay is due to a mycobactericidal effect of the peptide. These observations suggest that antimicrobial peptides may play an important role in host defence against MDR M. tuberculosis.
authors.affiliation: Swedish Institute for Infectious Disease Control, S-171 82 Solna.
authors.forename: C M
authors.initials: CM
authors.lastname: Linde
authors.forename: S E
authors.initials: SE
authors.lastname: Hoffner
authors.forename: E
authors.initials: E
authors.lastname: Refai
authors.forename: M
authors.initials: M
authors.lastname: Andersson
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D023181:Antimicrobial Cationic Peptides / Q000494:pharmacology*; D000995:Antitubercular Agents / Q000494:pharmacology*; D015169:Colony Count, Microbial; D004305:Dose-Response Relationship, Drug; D018432:Drug Resistance, Multiple / Q000502:physiology*; D006801:Humans; D008826:Microbial Sensitivity Tests; D009169:Mycobacterium tuberculosis / Q000187:drug effects*; D011506:Proteins / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D023181:Antimicrobial Cationic Peptides; D000995:Antitubercular Agents; D011506:Proteins; C072212:PR 39