Lina M Elsalem,
Jordan University of Science & Technology, Jordan
Title: Synergistic effects of antimicrobial peptide WLBU2 combined with antibiotics against multidrug-resistant bacteria associated with wound infections
Biography
Biography: Lina M Elsalem,
Abstract
Microbial resistance against conventional antibiotics is considered as a substantial health and economic burden to any health care system. Accordingly, research in the antimicrobial field has been directed toward the development of new agents such as the engineered cationic amphipathic peptide WLBU2. The aims of this study are: To evaluate the antimicrobial effects of WLBU2 against multi-drug resistant strains of bacteria including Gram-negative Enterobacter cloacae (ESBL+ve) and Gram-positive Methicillin-resistant Staphylococcus aureus (MRSA) and to assess whether synergistic effects can be achieved upon combination treatment of WLBU2 with conventional antibiotics. Clinical isolates of Enterobacter cloacae (ESBL+ve) and MRSA (n=30 for each) were obtained from wound infections in microbiology laboratories of the Jordanian Royal Medical Services. The Minimum Inhibitory Concentration (MIC) for WLBU2 and conventional antibiotics were determined using the microbroth dilution assay, according to CLSI-2017 guidelines. The antibiotics Ceftazidime, Ciprofloxacin and Ceftriaxone were used for Enterobacter cloacae (ESBL+ve), while MRSA was treated with Oxacillin and Erythromycin. The Fractional Inhibitory Concentration (FIC) index was utilized to determine the relationship between antimicrobial agents upon combination of sub-inhibitory concentration of WLBU2 with conventional antibiotics. The MIC for WLBU2 against Enterobacter cloacae (ESBL+ve) and MRSA ranged from (1.5 to 12.5) μg/ml and (0.78125 to 6.25) μg/ml, respectively. Synergistic and additive effects were achieved in Enterobacter cloacae (ESBL+ve) upon combination treatment with Ceftazidime (n=7/30, 17/30), Ciprofloxacin (n=9/30, 17/30) and Ceftriaxone (n=10/30, 17/30) respectively. Regarding MRSA, synergistic and additive effects were obtained with Erythromycin- WLBU2 treatment (n=2/30 and 10/30, respectively), while only additive effects were observed with Oxacillin- WLBU2 combination (n=14/30). Our data reveal that WLBU2 is a potent peptide with antimicrobial activity against Enterobacter cloacae (ESBL+ve) and MRSA. Our findings also support the development of WLBU2 in combination with conventional antibiotics with potential application for treatment of multidrug resistant bacteria associated with wound infections.