Physics Comes to the Aid of Medicine—Clinically-Relevant Microorganisms through the Eyes of Atomic Force Microscope

Abstract

Despite the hope that was raised with the implementation of antibiotics to the treatment of infections in medical practice, the initial enthusiasm has substantially faded due to increasing drug resistance in pathogenic microorganisms. Therefore, there is a need for novel analytical and diagnostic methods in order to extend our knowledge regarding the mode of action of the conventional and novel antimicrobial agents from a perspective of single microbial cells as well as their communities growing in infected sites, i.e., biofilms. In recent years, atomic force microscopy (AFM) has been mostly used to study different aspects of the pathophysiology of noninfectious conditions with attempts to characterize morphological and rheological properties of tissues, individual mammalian cells as well as their organelles and extracellular matrix, and cells’ mechanical changes upon exposure to different stimuli. At the same time, an ever-growing number of studies have demonstrated AFM as a valuable approach in studying microorganisms in regard to changes in their morphology and nanomechanical properties, e.g., stiffness in response to antimicrobial treatment or interaction with a substrate as well as the mechanisms behind their virulence. This review summarizes recent developments and the authors’ point of view on AFM-based evaluation of microorganisms’ response to applied antimicrobial treatment within a group of selected bacteria, fungi, and viruses. The AFM potential in development of modern diagnostic and therapeutic methods for combating of infections caused by drug-resistant bacterial strains is also discussed.

Quantification of Young's modulus of kaolin, sodalite and nanocomposite based polycaprolactone/sodalite using atomic force microscopy

“…These results are consistent with the literature [25], which reported significant variations in the calculation of the Young's modulus, despite using the same sample tested. The deviation of Young's modulus for Kaolin obtained in the present study is significant when compared with the reference literature [31,32]. It can be explained on the basis that rough surfaces and pores on kaolin particles can cause the indenter to interact unevenly, affecting the contact area.…”

“…During indentation, the resulting forces may damage the cantilever and/or the sample or the tip [29][30][31]. Therefore, it is considered necessary to resort to the proposed method to avoid this problem.…”

Atomic force microscopy analysis of Pel polysaccharide- and type IV pili-mediated adhesion of Pseudomonas aeruginosa PA14 to an abiotic surface

“…14–16 Several other studies have examined biofilm-related factors by AFM, including pili, adhesins and polysaccharides. 15,17–25 Additionally, using a laser trap, Maier, O'Toole and colleagues demonstrated that the retraction force of TFP of P. aeruginosa could exert a force of ∼30 pN. 26 Finally, we examined the role of TFP in adhesion of P. aeruginosa to a hydrophobic surface, revealing that a TFP could generate strong adhesive forces in a time-dependent manner and that a single pili can sustain forces up to 250 pN.…”

Prospects and Challenges for Graphene Drums As Sensors Of Individual Bacteria

“…Furthermore, in eukaryotes intracellular organelles, such as mitochondria, which are responsible for energy generation, also show nanomotion ( 42 ). Detecting nanomotion using fluorescent labelled products or organelles ( 43 ) is an interesting way to further explore nanomotion causes which might lead to new insights into the root cause.…”