The mechanism of action of Glycopeptide Antibiotics is unique compared to other classes of antibiotics. Glycopeptide antibiotics work by binding to the D-alanine-D-alanine terminus of peptidoglycan in the bacterial cell wall, which prevents the cross-linking of peptidoglycan strands. This ultimately leads to bacterial cell death. This mechanism of action is different from that of beta-lactam antibiotics, which work by inhibiting the synthesis of peptidoglycan. Vancomycin, the most commonly used Glycopeptide Antibiotics, is primarily used to treat serious infections caused by Gram-positive bacteria, including MRSA. Vancomycin is not effective against Gram-negative bacteria because it cannot penetrate the outer membrane of these bacteria.