Bactericidal activity of micromolar N-chlorotaurine: Evidence for its antimicrobial function in the human defense system

• Published in: Antimicrobial agents and chemotherapy Vol. 44; no. 9; pp. 2507 - 2513
• Main Authors: NAGL, M, HESS, M. W, PFALLER, K, HENGSTER, P, GOTTARDI, W
• Format: Journal Article
• Language: English
• Published: Washington, DC American Society for Microbiology 01.09.2000
• Subjects: Adult; Anti-Bacterial Agents - pharmacology; Antibacterial agents; Antibiotics. Antiinfectious agents. Antiparasitic agents; Biological and medical sciences; Chloramines - metabolism; Chloramines - pharmacology; Escherichia coli; Granulocytes - metabolism; Half-Life; Humans; Hydrogen-Ion Concentration; In Vitro Techniques; Medical sciences; Microbial Sensitivity Tests; Microscopy, Electron; N-Chlorotaurine; Oxidants - metabolism; Pharmacology. Drug treatments; Proteus mirabilis; Pseudomonas aeruginosa; Staphylococcus aureus; Staphylococcus aureus - drug effects; Staphylococcus aureus - ultrastructure; Staphylococcus epidermidis; Streptococcus pyogenes; Susceptibility; Taurine - analogs & derivatives; Taurine - pharmacology; Pseudomonadales; Granulocyte; Tosylchloramide sodium; Oxidant; Pseudomonas; Blood; Staphylococcus; Dose activity relation; Proteus; pH; Bacteria; Micrococcales; Pseudomonadaceae; Micrococcaceae; Mechanism of action; Peritonitis; Enterobacteriaceae; Immune system; Human; Escherichia; Healthy subject; Rodentia; In vitro; Biological activity; Streptococcaceae; In vivo; Vertebrata; Blood cell; Mammalia; Sensitivity resistance; Streptococcus; Mouse; Abdominal disease; Animal; Antibacterial agent
• ISSN: 0066-4804; 1098-6596
• DOI: 10.1128/AAC.44.9.2507-2513.2000

N-Chlorotaurine, the main representative of long-lived oxidants found in the supernatant of stimulated granulocytes, has been investigated systematically with regard to its antibacterial activity at different physiological concentrations for the first time. N-Chlorotaurine (12.5 to 50 microM) demonstrated a bactericidal effect i.e., a 2 to 4 log(10) reduction in viable counts, after incubation at 37 degrees C for 6 to 9 h at pH 7.0, which effect was significantly enhanced in an acidic milieu (at pH 5. 0), with a 3 to 4 log(10) reduction after 2 to 3 h. Moreover, bacteria were attenuated after being incubated in N-chlorotaurine for a sublethal time, as demonstrated with the mouse peritonitis model. The supernatant of stimulated granulocytes exhibited similar activity. Transmission electron microscopy revealed changes in the bacterial cell membrane and cytoplasmic disintegration with both reacting systems, even in the case of a mere attenuation. The results of this study suggest a significant bactericidal function of N-chlorotaurine and other chloramines during inflammation.