Since the discovery of antibiotics in the 1920s, the treatment of bacterial infections in humans and animals has emerged as a revolutionary possibility. Antibiotics are drugs produced naturally by bacteria or fungi to defend themselves from other bacteria through death or inhibition of reproduction (1). Since their discovery, antibiotics have been diversified into many different forms and classes, divided by mode of action. Glycopeptides are a class of antibiotics composed of cyclic or polycyclic glycosylated nonribosomal peptides that inhibit cell wall synthesis in susceptible bacteria (2). However, it was soon discovered that the use of these antibiotic drugs would lead to antibiotic resistance. This article will discuss the history, function, and resistance associated with vancomycin, a glycopeptide antibiotic. History Vancomycin, which is a specific antibiotic that falls within the subset of glycopeptide antibiotics, was first discovered from a soil sample in the jungle of Bornea by Dr. E. C. Kornfield during an antimicrobial research program in 1953 (2). Vancomycin is a bactericide harvested from a strain of bacteria known as Streptomyces orientalis, and at the time of its initial mass production in the 1950s, it was found to contain many impurities which may have led to its early ototoxic and nephrotoxic properties which make it a secondary drug after initial approval by the FDA (3). However, it has since been purified to a higher degree and those properties have dissipated leaving a very pure, low toxicity antimicrobial agent. It is now used as a last resort antibiotic and especially administered intravenously; however, studies are underway to interpret how best to administer the drug as a new vancomycin-resistant species h...... half of article ......heptide-resistant operon from Enterococcus faecalis revisited. Mol Microbiol2003;50:931-48(18) Courvalin, Patrice. (2006). Vancomycin resistance in Gram-positive cocci. Clinical Infectious Diseases, 42 (Supplement 1), S25-S34. doi: 10.1086/491711(19) Arthur M, Reynolds P, Courvalin P Glycopeptide Resistance in enterococci.TrendsMicrobiol 1996;4:401-7.(20) Arthur M, Depardieu F, Cabanie L, Reynolds P, Courvalin P. Requirement of the D,D-peptidases VanY and VanX for glycopeptide resistance in enterococci. MolMicrobiol 1998;30: 819-30(21) Reynolds PE, Courvalin P. Resistance to vancomycin by synthesis of precursors terminating in D-alanyl-D-alanine. Antimicrob Agents Chemother 2005;49:21-5.(22) Depardieu F, Reynolds PE, Courvalin P. Vancomycin-resistant Enterococcus faecium type VanD 10/96A. Chemotherapeutic antimicrobial agents 2003;47:7-18.