BioAFM Journal Club

Micro- to Nano-Scale Chemical and Mechanical Mapping of Antimicrobial-Resistant Fungal Biofilms

by Duy Quang Pham, Saffron J. Bryant, Samuel Cheeseman, Louisa Z. Y. Huang, Gary Bryant, Madeleine F. Dupont, James Chapman, Christopher C. Berndt Jitraporn (Pimm) Vongsvivut, Russell J. Crawford, Vi Khanh Truong, Andrew S. M. Ang, and Aaron Elbourne

Key Points

  • A combination of atomic force microscopy (AFM), instrumented nanoindentation, and Synchrotron ATR-FTIR measurements can be used for characterizing the compositions, and in-turn nanomechanical properties, of fungal biofilms.


This review appeared in the July 2021 edition of the BioAFM Journal Club — a monthly email brief highlighting leading-edge research and the latest discoveries supported by Bruker BioAFM technology. Subscribe now.

Nanoscale, 2020,12, 19888-19904
DOI: 10.1039/D0NR05617K

This article highlights AFM-based research on drug-resistant microorganisms and their biofilms. The researchers combined AFM with nanoindentation and synchrotron-based ATR-FTIR spectral mapping to quantify the nanomechanical and bio-chemical differences between the mature biofilms of various fungal species: Candida albicans, Cryptococcus neoformans and two antifungal resistant sub-species of C. neoformans.

In this work, the NanoWizard 4 bioAFM and Hysitron TI Premier nanoindenter were used to perform imaging and nanoscale modulus mapping tests, while ATR-FTIR micro-spectroscopy analysed the spatio-chemical composition of the four biofilm systems. The AFM measurements provided high-resolution images and highlighted the morphological differences between the four fungal cell types, suggesting that antifungal resistance in the species studied causes visible and measurable changes in their cellular morphology. Bulk nanoindentation measurements highlighted the difference in the storage modulus values between resistant and sensitive fungal strains, while no significant differences in the surface adhesion of the biofilms of the species were observed.

      KEY TERMS:

  • Fungi; Biofilm; Fungal Biofilm; Antifungal Resistance; Anisotropic Material; Polymeric Extracellular Matrix (ECM)