Atomic force microscopy and chemical force microscopy of microbial cells

Area of Science:

• Microbiology
• Biophysics
• Nanotechnology

Background:

• Atomic force microscopy (AFM) offers nanometer-resolution imaging of microbial cell surfaces under physiological conditions.
• Chemical force microscopy (CFM) and single-molecule force spectroscopy map cell surface chemistry and receptors, revealing structure-function relationships.

Purpose of the Study:

• To present detailed protocols for analyzing Aspergillus fumigatus spores using real-time AFM and CFM.
• To provide guidelines for reliable experimental execution and data interpretation.

Main Methods:

• Utilizing porous polymer membranes for single live cell immobilization.
• Modifying gold-coated AFM tips with alkanethiols for CFM measurements.
• Employing real-time AFM imaging and CFM for spore analysis.

Main Results:

• Established protocols for high-resolution imaging and chemical mapping of Aspergillus fumigatus spores.
• Demonstrated the effectiveness of specific immobilization and tip modification techniques.
• Provided recommendations for optimizing recording conditions and data interpretation.

Conclusions:

• The presented protocols enable detailed analysis of microbial cell surfaces with AFM and CFM.
• These methods offer valuable insights into the structure-function relationships of pathogenic fungi like Aspergillus fumigatus.
• The protocols are designed for efficient execution by trained AFM users within 2-3 days.