In vitro effect of the iron chelator deferiprone on the antimicrobial susceptibility and biofilms of Burkholderia pseudomallei

Abstract

This study evaluated the effect of the iron chelator deferiprone (DFP) on antimicrobial susceptibility and biofilm formation and maintenance by Burkholderia pseudomallei. Planktonic susceptibility to DFP alone and in combination with antibiotics was evaluated by broth microdilution and biofilm metabolic activity was determined with resazurin. DFP minimum inhibitory concentration (MIC) range was 4–64 µg/mL and in combination reduced the MIC for amoxicillin/clavulanate and meropenem. DFP reduced the biomass of biofilms by 21 and 12% at MIC and MIC/2, respectively. As for mature biofilms, DFP reduced the biomass by 47%, 59%, 52% and 30% at 512, 256, 128 and 64 µg/mL, respectively, but did not affect B. pseudomallei biofilm viability nor increased biofilm susceptibility to amoxicillin/clavulanate, meropenem and doxycycline. DFP inhibits planktonic growth and potentiates the effect of β-lactams against B. pseudomallei in the planktonic state and reduces biofilm formation and the biomass of B. pseudomallei biofilms.

Keywords:

• Burkholderia pseudomallei
• deferiprone
• iron chelator
• biofilms

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Council for Scientific and Technological Development (CNPq, Brazil, process number 310826/2020-9; 405312/2021-0) and Coordination for the Improvement of Higher Education Personnel (CAPES, Brazil, 88887.474811/2020-00).