Antimicrobial resistant (AMR) infections are already the third leading cause of death in the USA and are predicted to kill 50 million people per year by 2050. It is the next pandemic starting already. We have been using our capability to track nanoparticles in an optical microscope [see ‘Slow moving nanoparticles‘ on December 13th, 2017 and ‘Nano biomechanical engineering of agent delivery to cells‘ on December 15th, 2021] to track individual bacterium as they interact with surfaces to form biofilms. Bacterial biofilms are complex colonies of bacteria that are highly resistant to antimicrobial agents and can cause life-threatening infections. We have used our label-free, real-time tracking capabilities to explore the dynamics and adhesion of bacteria to surfaces and found that viable bacteria adhered to the surface but continue to move with rotary or sliding motions depending on the mechanics of their attachment to the surface. Bacteria that were killed by contact with the surface did not move once they were attached to the surface. The image shows examples of these motions from our paper published last month. Our ability to detect these differences in the dynamics of bacteria will allow us to detect the onset of the formation of biofilms and to quantify the efficacy of antimicrobial surfaces and coatings.
Image: Figure 4 – Tracks (yellow lines) of the sections (purple circles) of four E. coli bacteria experiencing: (a) random diffusion above the surface; (b) rotary attachment; (c) lateral attachment; (d) static attachment. The dynamics of the four bacteria was monitored for approximately 20 s. The length of the scale bars is 5 μm. From Scientific Reports, 12:18146, 2022.
Giorgi F, Curran JM & Patterson EA, Real-time monitoring of the dynamics and interactions of bacteria and the early-stage formation of biofilms, Scientific Reports, 12:18146, 2022.