Pharmacology · Class
Glycopeptides !
Large antibiotics that block cell-wall building in gram-positive bacteria, including MRSA; vancomycin is the classic member.
Updated 2026-11-01
What they are
Glycopeptides and their lipid-bearing relatives (lipoglycopeptides) act only on gram-positive bacteria. They are the main option for methicillin-resistant Staphylococcus aureus (MRSA) and for patients who cannot receive β-lactams.
Mechanism of action
They bind tightly, without a covalent bond, to the D-alanyl–D-alanine end of the peptidoglycan building block. Sitting on that end, they physically block both the polymerization step (transglycosylation) and the cross-linking step (transpeptidation), so the wall cannot grow. They are too large to cross the outer membrane of gram-negative bacteria.
Target: D-Ala–D-Ala terminus of peptidoglycan precursors
Drugs in this class
- VancomycinAn intravenous glycopeptide for serious gram-positive infections such as MRSA; given by mouth only for C. difficile…D-Ala–D-Ala terminus of the peptidoglycan precursor
- DalbavancinA long-acting lipoglycopeptide for gram-positive skin infections, including MRSA, given as one or two infusions.D-Ala–D-Ala terminus of the peptidoglycan precursor
Others in the class
- teicoplanin
- oritavancin (lipoglycopeptide)
- telavancin (lipoglycopeptide)
Test yourself
Think of the answer, then tap the question to see it.
Which molecular target do glycopeptides bind?
The D-alanyl–D-alanine end of the peptidoglycan precursor; by covering it they block polymerization and cross-linking of the cell wall.
Why are glycopeptides useless against Escherichia coli?
They are too large to cross the outer membrane of gram-negative bacteria, so they never reach the cell wall.
How do vancomycin-resistant enterococci escape the drug?
They replace D-Ala–D-Ala with D-Ala–D-lactate (or D-Ala–D-serine), a terminus that vancomycin binds poorly.
Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.
Sources: Goodman & Gilman's The Pharmacological Basis of Therapeutics, 14th ed., ch. 58 (McGraw Hill, 2023); DailyMed - VANCOMYCIN HYDROCHLORIDE injection, powder, lyophilized, for solution (DailyMed (U.S. National Library of Medicine), 2026); RCSB PDB - 1FVM: Complex of vancomycin with DI-acetyl-LYS-D-ALA-D-ALA (RCSB Protein Data Bank, 2026).
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Representative model, for educational purposes only.