Title:Levofloxacin and Indolicidin for Combination Antimicrobial Therapy
Volume: 12
Issue: 1
Author(s): Khairunnisa Abdul Ghaffar, Waleed M. Hussein, Zeinab G. Khalil, Robert J. Capon, Mariusz Skwarczynski and Istvan Toth
Affiliation:
Keywords:
Antibiotic, levofloxacin, indolicidin, TAT peptide, conjugation.
Abstract: Despite the increasing need for antibiotics to fight infectious diseases, fewer new antibiotics are
available on the market. Unfortunately, developing a new class of antibiotics is associated with high commercial
risk. Therefore, modification or combination of existing antibiotics to improve their efficacy is a promising
strategy. Herein, we conjugated the antibiotic, levofloxacin, with two peptides, i.e. an antimicrobial peptide
indolicidin and a cell penetrating peptide (TAT). Glycolic acid and glycine linkers were used between
levofloxacin and peptides. We developed an optimized condition for coupling of levofloxacin via its carboxylic group to
glycolic acid using solid phase peptide synthesis (SPPS). Antibacterial and haemolytic assays were carried out on the conjugates
and only the levofloxacin-indolicidin conjugate demonstrated moderate antibacterial activity. Interestingly, physical
mixture of levofloxacin and indolicidin showed improvement in the activity against Gram-positive bacteria.
