Potentiation of Antibiotic Activity by a Novel Cationic Peptide: Potency and Spectrum of Activity of SPR741.

Potentiation of Antibiotic Activity by a Novel Cationic Peptide: Potency and Spectrum of Activity of SPR741. Antimicrob Agents Chemother. 2017 May 22;: Authors: Corbett D, Wise A, Langley T, Skinner K, Trimby E, Birchall S, Dorali A, Sandiford S, Williams J, Warn P, Vaara M, Lister T Abstract Novel approaches to the treatment of multi-drug resistant Gram-negative bacterial infections are urgently required. One approach is to potentiate the efficacy of existing antibiotics whose spectrum of activity is limited by the permeability barrier presented by the Gram-negative outer membrane. Cationic peptides derived from polymyxin B have been used to permeabilize the outer membrane, granting antibiotics that would otherwise be excluded access to their targets. We assessed the in vitro efficacy of combinations of SPR741 with conventional antibiotics against Escherichia coli, Klebsiella pneumoniae, and Acinetobacter baumannii Of 35 antibiotics tested, the MICs of eight were reduced 32- to 8,000-fold against E. coli and K. pneumoniae in the presence SPR741. The eight antibiotics - azithromycin, clarithromycin, erythromycin, fusidic acid, mupirocin, retapamulin, rifampicin, and telithromycin - had diverse targets and mechanisms of action. Against A. baumannii, similar potentiation was achieved with clarithromycin, erythromycin, fusidic acid, retapamulin and rifampicin. Susceptibility testing of the most effective antibiotic-SPR741 combinations w...
Source: Antimicrobial Agents and Chemotherapy - Category: Microbiology Authors: Tags: Antimicrob Agents Chemother Source Type: research