The wings of some insects, such as the cicada and dragonfly, possess nanopillar structures that kill bacteria upon contact. However, to date, the precise mechanisms that cause bacterial death have been unknown.
Using a range of advanced imaging tools, functional assays, and proteomic analyses, a study by the University of Bristol has identified new ways in which nanopillars can damage bacteria. These important findings will aid the design of better antimicrobial surfaces for potential biomedical applications such as medical implants and devices that aren’t reliant on antibiotics.
Bo Su, Professor of Biomedical Materials at the University of Bristol’s Dental School, who authored the research said: “In this work, we sought to better understand nanopillar-mediated bactericidal mechanisms. The current dogma is that nanopillars kill bacteria by puncturing bacterial cells, resulting in lysis. However, our study shows that the antibacterial effects of nanopillars are actually multifactorial, nanotopography- and species-dependent.
“Alongside deformation and subsequent penetration of the bacterial cell envelope by nanopillars, particularly for Gram-negative bacteria, we found the key to the antibacterial properties of these nanopillars might also be the cumulative effects of physical impedance and induction of oxidative stress.
“We can now hopefully translate this expanded understanding of nanopillar-bacteria interactions into the design of improved biomaterials for use in real-world applications.”