| Popis: |
A novel biocide, AB569 containing acidified nitrite (A-NO2-) and Ethylenediaminetetraacetic Acid (EDTA) combined, has demonstrated bactericidal activity in previous studies with Pseudomonas aeruginosa (Pa) (1) Multi-Drug Resistant Organisms (MDRO) present a challenge to the all-inclusive killing abilities of AB569. Thus, Acinetobacter baumannii (Ab) and Acinetobacter spp. present a model with widely known resistance to antibiotics. Killing studies with AB569 reveal bactericidal action with extended exposure time, 24 to 48 hr, and effective results at key concentrations during shorter inhibitory exposure time, 1 mM EDTA and 32 mM A-NO2-. AB569 as a treatment for Ab is a viable option to prevent bacterial growth, with tests revealing average Fractional Inhibitory Concentration (FIC) concentrations of 0.25 mM EDTA plus 4 mM A-NO2 - across several reference and clinicalstrains. In addition, toxicity testing on Adult Human Dermal Fibroblasts (HDFa) revealed an upper toxicity limit of 3 mM EDTA plus 64 mM A-NO2 -. AB569 FIC concentrations are within the HDFa cell toxicity range for effective Ab and Acinetobacter spp. treatment. Following treatment with AB569, quantitative PCR revealed up-regulated siderophore production on EDTA treated sample in Siderophore Biosynthesis Non-Ribosomal Peptide Synthetase Module (SBNRPSM) and Siderophore Biosynthesis Protein, Monooxygenase (SBPM) genes compared to untreated control during inhibitory conditions, which was not observed with AB569 treatment. Treating Ab infections with AB569 at inhibitory concentrations reveals the potential clinical benefit of preventing Ab from gaining a growth advantage early in a mixed infection followed by bactericidal activity with extended treatments |
