title: Bactericidal activity of the organo-tellurium compound AS101 against Enterobacter cloacae.
abstract: OBJECTIVE
  The antibacterial effect of the organo-tellurium compound AS101 on the Gram-negative bacterium Enterobacter cloacae is shown in this study for the first time.
  
  
  METHODS
  The antimicrobial effect of the drug was shown by inhibition of growth, by inhibition of biofilm formation and by its ability to penetrate the bacterial cell and to cause damage and ultrastructural changes.
  
  
  RESULTS
  AS101 was found to be a bactericidal drug with MICs and MBCs of 9.4 mg/L. It inhibits bacterial growth and causes a six orders of magnitude decrease in viability in a protein-rich medium, but not in a protein-poorer medium, unless 2-mercaptoethanol is added. Subinhibitory concentrations inhibit motility and biofilm formation. AS101 enters the bacterium through its porins and causes bacterial damage to Na(+)/K(+) pumps and leakage of potassium, phosphorous and sulphur. Ultrastructural changes within the bacterial cell and on its surface demonstrate an incomplete surface with a concavity in the centre that looks like a hole from which aggregates are liberated as well as cell lysis.
  
  
  CONCLUSIONS
  AS101 has antibacterial activity, which may be useful against E. cloacae and other species of Enterobacteriaceae as a substitute for current antibiotics that have become ineffective due to increasing bacterial resistance.
authors.affiliation: Mina and Everard Goodman Faculty of Life Sciences,  Bar-Ilan University, Ramat-Gan 52900,  Israel.
authors.forename: Miriam
authors.initials: M
authors.lastname: Daniel-Hoffmann
authors.forename: Benjamin
authors.initials: B
authors.lastname: Sredni
authors.forename: Yeshayahu
authors.initials: Y
authors.lastname: Nitzan
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D018441:Biofilms / Q000187:drug effects; D016972:Enterobacter cloacae / Q000187:drug effects* / Q000502:physiology / Q000648:ultrastructure; D005030:Ethylenes / Q000494:pharmacology*; D006801:Humans; D008826:Microbial Sensitivity Tests; D050296:Microbial Viability / Q000187:drug effects*; D013499:Surface Properties / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D005030:Ethylenes; C054105:ammonium trichloro(dioxoethylene-O,O'-)tellurate