Vancomycin is an aminoglycoside antibiotic, used in the treatment of infections caused by Gram-positive bacteria. vancomycin is not active against Gram-negative bacteria (except some non-gonococcal species of Neisseria). The main target of this antibiotic is the D-alanyl-D-alanine terminal dipeptide of peptidoglycan precursors, used by bacteria for constructing their cell walls. This prevents the reaction used to link peptidoglycan precursors together from taking place. Vancomycin binds with the substrate, not the enzyme, in contrast to the way penicillin inhibits peptidoglycan synthesis.The large hydrophilic molecule is able to form hydrogen bond interactions with the terminal D-alanyl-D-alanine moieties of the NAM/NAG-peptides. Under normal circumstances, this is a five-point interaction. This binding of vancomycin to the D-Ala-D-Ala prevents cell wall synthesis in two ways. It prevents the synthesis of the long polymers of N-acetylmuramic acid (NAM) and N-acetylglucosamine (NAG) that form the backbone strands of the bacterial cell wall, and it prevents the backbone polymers that do manage to form from cross-linking with each other.Solubility:Clear, freely soluble in water, slightly soluble in alcoholpH (50mg/ml):2.5-4.5Water (Karl Fisher):≤5%Heavy Metals:≤0.003%Residual Solvents (Ethanol):≤0.5%Bacterial Endotoxins:≤0.33IU/mgRelated Substances:Monodechlorovancomycin: ≤4.7%Other peak impurity: ≤4%Storage and Stability:Lyophilized powder may be stored at 4°C. Stable for 6 months after receipt.
