Table 3c: Glycopeptides, analogs and synthetic glycopeptides.
• A cyclic anionic peptide with a decanoyl fatty acid side chain that interacts with calcium to form Ca-Dap complex which binds to negatively charged phosphatidylglycerol groups in cell membrane causing cell death through depolarisation, permeabilization and leakage of ions .
• Daptomycin resistance (DapR) results during prolonged therapy from complex mechanisms. One well established mechanism is through the Multiple Peptide Resistance Factor protein (MprF). MprF confers broad-range resistance to host antimicrobial peptides, thereby promoting S. aureus cell virulence and pathogenicity .
• IDSA recommends high-dose daptomycin, if the isolate is susceptible, in combination with another agent (e.g., gentamicin, rifampin, linezolid, TMP-SMX, or a beta-lactam antibiotic).
• Recommended for treatment of high bacterial density or serious infections like endocarditis.
• Resistance is emerging in all of the targeted pathogens, but the resistance rates are currently low.
• Semisynthetic lipoglycopeptides.
• Inhibits peptidoglycan biosynthesis and cause cell membrane damages .
• Approved for ABSSI. Use is limited because of the need for IV administration.
• Contraindicated in pregnancy.
• Oritavancin is an analog of vancomycin that has the main heptapeptide core with other unique substitutions.
• Approved for ABSSI.
• It shows promise for the treatment of serious infections and activity against daptomycin-nonsusceptible S. aureus .