Related Experiment Video
Updated: Jul 20, 2025

Time-lapse Imaging of Bacterial Swarms and the Collective Stress Response
Published on: May 23, 2020
Time-dependent plastic behavior of bacteria leading to rupture
Reshma Y Siddiquie1, Kuldeep Sharma2, Anirban Banerjee2
1Department of Mechanical Engineering, Indian Institute of Technology, Bombay, India.
Abstract:
A study of the mechanical response of bacteria is essential in designing an antibacterial surface for implants and food packaging applications. This research evaluated the mechanical response of Escherichia coli under different loading conditions. Indentation and prolonged creep tests were performed to understand their viscoelastic-plastic response. The results indicate that varying loading rates from 1 μm/s to 5 μm/s show an increase in modulus of 182% and 90%, calculated in the loading and unloading cycles, respectively, and a decrease in adhesion force by 42%. However, on varying loads from 5 nN to 25 nN, nominal change is observed in both modulus and adhesion force. The rupture curve at 100 nN load shows elastic and a small plastic deformation accompanied by a sharp peak indicating the cell wall rupture. The rupture force at the peak was found to be 34.38 ± 5.15 nN, irrespective of the loading rate, making it a failure criterion for bacteria rupture. The creep response of bacteria increases (for 6 s) and then remains constant (for 15 s) with time, indicating that a standard linear solid (SLS) model applies to this behavior. This work attempts to evaluate the mechanical properties of E. coli bacteria focusing on its rupture by contact killing mechanism.
Related Concept Videos
Stringent Response in E. coli
Plastic Behavior
Other Stress Responses in Bacteria
Bacterial Signaling
Coordination of Gene Expression Processes in Bacteria
Gene Regulation During Sporulation

