Occidiofungin's Chemical Stability and In Vitro Potency against Candida Species

Department of Biological Sciences, Mississippi State University, Mississippi State, Mississippi, USA.
Antimicrobial Agents and Chemotherapy (Impact Factor: 4.48). 11/2011; 56(2):765-9. DOI: 10.1128/AAC.05231-11
Source: PubMed


Occidiofungin is a cyclic glyco-lipopeptide produced by Burkholderia contaminans. MICs against Candida species were between 0.5 and 2.0 μg/ml. Occidiofungin retains its in vitro potency in the presence of 5% and 50% human serum with a minimal lethal concentration (MLC) of 2 and 4 μg/ml, respectively.
Time-kill and postantifungal effect (PAFE) experiments of occidiofungin against Candida albicans were performed. The results demonstrate that occidiofungin is fungicidal. Occidiofungin was also found to be a very stable
molecule. It is resistant to extreme temperatures and pH and maintains its activity following exposure to gastric proteases.

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    • "These results indicate that occidiofungin is distinctive from the four existing classes of clinically used antifungal drugs and that occidiofungin's potential as a therapeutic agent warrants further investigation. The TC 50 (toxic concentration resulting in 50% cell death) against mouse fibroblasts was 3 µM, which is similar to the MICs against Candida species [1]. Minimum inhibitory concentrations (MICs) of occidiofungin against Candida species are submicromolar to micromolar, which is similar in activity to echinocandins and amphotericin B [1] [9] [10]. "

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