INTERACTION OF SILVER-NITRATE WITH READILY IDENTIFIABLE GROUPS - RELATIONSHIP TO THE ANTIBACTERIAL ACTION OF SILVER IONS

Microbiologically it was demonstrated that amino acids, e.g. cysteine (CySH), and other compounds, e.g. sodium thioglycollate, containing th iol groups neutralized the activity of silver nitrate against Pseudomo nas aeruginosa PAOl. Amino acids with disulphide bonds were inactive, with the exception of L-cystine dimethyl ester, as were all amino acid s with no sulphur groups. Iodoacetamide reacted with CySH to produce a CyS-acetamide complex that was unable to quench the activity of Ag+. Chemical analyses using cyclic voltammetry demonstrated that high coor dination numbers (3.1) were obtained with thiol-containing amino acids and low numbers (0.28-0.4) with other amino acids. Both microbiologic ally and chemically, the results imply that interaction of Ag+ with th iol groups plays an essential role in bacterial inactivation.