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Nanopillar surface mediates antibacterial effects via cell impedance, penetration and induction of oxidative stress

ABSTRACT: Abstract. The adhesion of bacteria to medical implants and formation of biofilms is a growing healthcare problem that accounts for a significant proportion of hospital-acquired infections globally. Insects, including cicada and dragonfly, have evolved nanoprotrusions-protruding arrays on their wings that rupture bacteria on contact. This has inspired the design of antibacterial implant surfaces with insect wing mimetic nanopillarsarrays . Here we characterise the physiological and morphological responses of bacteria to dragonfly wing mimetic nanowirenanopillars arrays, with the aim of determining the mechanistic basis for antibacterial activity. Dragonfly wing mimetic nanowirenanopillars arrays induce deformation and penetration of Gram-positive and Gram-negative bacterial envelopes, but do not rupture or lyse bacteria. NanowireNanopillars also have capacity to impede bacterial division and trigger reactive oxygen species production oxidative stress responses, leading to the increased abundance of oxidative stress proteins. NanowireNanopillar-induced oxidative stress represents a novel antibacterial mechanism of biomimetic nanotopographies .arrays Better understanding of this could prove invaluable for enhancing the bactericidal performance of nanotextured materials for next generation antibacterial medical implants

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ORGANISM(S): Escherichia Coli Bacteria Staphylococcus Aureus

SUBMITTER: Joshua Jenkins

LAB HEAD: Bo Su

PROVIDER: PXD017078 | Pride | 2020-05-27

REPOSITORIES: Pride

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Antibacterial effects of nanopillar surfaces are mediated by cell impedance, penetration and induction of oxidative stress.

Jenkins J J Mantell J J Neal C C Gholinia A A Verkade P P Nobbs A H AH Su B B

Nature communications 20200402 1

Some insects, such as dragonflies, have evolved nanoprotrusions on their wings that rupture bacteria on contact. This has inspired the design of antibacterial implant surfaces with insect-wing mimetic nanopillars made of synthetic materials. Here, we characterise the physiological and morphological effects of mimetic titanium nanopillars on bacteria. The nanopillars induce deformation and penetration of the Gram-positive and Gram-negative bacterial cell envelope, but do not rupture or lyse bacte ...[more]

PMID: 32242015

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