Escherichia coli (ATCC 13706) is susceptible to retapamulin, an antimicrobial semisynthetic derivative of pleuromutilin

  • Author(s) / Creator(s)
  • Antimicrobial resistance (AMR) is a top 10 global threat to human health, as well as a major global health threat to animals and the environment. AMR can reduce the efficacy of antibiotic therapeutics, making treatment of bacterial infections difficult, expensive, and sometimes impossible. The increasing and wide-spread use of antibiotics has led to their global-scale misuse and abuse, resulting in the exponential emergence of antibiotic-resistant bacterial strains at alarming rates. The lack of speed in the development of new therapeutics for resistant bacteria is also a contributing factor to this global issue. Pleuromutilin, a diterpene natural product first isolated from the fungus Clitopilus passeckerianus, has been shown to be a potent inhibitor of Gram-positive (Staphylococcus aureus) and some Gram-negative bacteria (Haemophilus influenzae) by electively inhibiting bacterial translation. Retapamulin, the first drug in the new class of pleuromutilin antibiotics to be approved for human use as a topical antibiotic, was effective against Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA) in clinical trials. Although most strains of the Gram-negative bacteria Escherichia coli (E. coli) are harmless, several strains have developed antibiotic resistance. E. coli (ATCC 13706) is commonly found in wastewater, therefore susceptible to becoming antibiotic resistant. Given the observed inhibitory effects of retapamulin and pleuromutilin against Gram-positive bacteria and some Gram-negative bacteria, respectively, we hypothesize that retapamulin hinders the growth of E. coli (ATCC 13706). After performing the Kirby Bauer disk diffusion assay, we found that retapamulin inhibits E. coli at 500 ug/ml and it plateaus at 2500 ug/ml (ANOVA, df (9,20), F=121.3, p=1.8x10exp-15). We will also assess the minimum inhibitory and bactericidal concentrations. Thus far, our study suggests that E. coli ATCC 13706 is susceptible to retapamulin.

  • Date created
  • Subjects / Keywords
  • Type of Item
    Conference/Workshop Poster
  • DOI
  • License
    Attribution-NonCommercial 4.0 International