Submitted to: Congress of European Microbiology
Publication Type: Abstract only
Publication Acceptance Date: 3/13/2009
Publication Date: 5/16/2009
Citation: Svetoch, E.A., Eruslanov, B.V., Kovalev, Y.N., Mitsevichq, E.V., Mitsevich, I.P., Levchuk, V.P., Fursova, N.K., Perelygin, V.V., Stepanshin, Y.G., Seal, B.S., Stern, N.J. 2009. Antimicrobial activities of bacteriocins E50-52 and B602 against MRSA and other nosocomial infections. Congress of European Microbiology. Helsinki, Finland. May 16-19,2009; ECCMID CD; Abstract R2136. Interpretive Summary:
Technical Abstract: Our objective was to determine the antimicrobial activities of previously published bacteriocins E50-52 and B602 against methicillin resistant Staphylococcus aureus (MRSA) and other prominent nosocomial bacterial infections. methods: Several Russian hospitals were enlisted into the study from 2003 to 2007 and the hospitals supplied isolates of Acinetobacter spp. (n=11), Citrobacter freundii (n=8), Escherichia coli (n=9), Klebsiella pneumoniae (n=10), Proteus spp. (n=6), Pseudomonasa aeruginosa (n=10), and Staphylococcus aureus (n=10). Susceptibilities were determined by Kirby-Bauer disc-diffusion assays using 12 antibiotics belonging to different functional groups. Minimal inhibitory concentrations (MICs) were determined for 19 antibacterials. Extended spectrum beta-lactamase (ESBL) genes were detected using a standardized polymerase chain reaction (PCR) method. results: The amino acid sequences, molecular weights and the isoelectric points of both bacteriocins E50-52 and B602 were determined as being consistent with class IIa characteristics, containing 39 and 29 amino acid residues, molecular weights of 3,932 and 3,864 Da, and pI values of 8.5 and 7.2, respectively. ESBL genes were detected in 27 of the 32 C. freundii, E. coli, K. pneumoniae, Proteus mirabilis isolates and, were not detected in the Acinetobacter spp., Ps. aeruginosa or S. aureus isolates. The antibiotic profiles of the 64 diverse isolates manifested substantial resistance, as associated with the poor clinical outcomes of the infected individuals. The MIC values of the same isolates ranged from < 0.025 to 1.56 mg/ml for bacteriocin B602 and 0.05 to 6.25 mg/ml for bacteriocin E50-52. In conclusion, for the 64 diverse clinical isolates tested, antibiotic resistance was unfortunately high while the susceptibility to the bacteriocins tested was remarkably good. The potentials for application of bacteriocins in clinical settings as therapeutic agents appear quite promising.