Since the 1940s, antibiotics have been used in treating people with an infectious diseases brought by bacteria. These drugs have greatly lowered illness and death from tuberculosis and pneumonia.

However, some antibiotics have been used so widely and for so long that some strains of disease-causing bacteria have become resistant, making the treatments less effective. During the previous years, the rates of drug-resistant infections have increased, which concerned global health experts.

Microscale Spikes Attached to Titanium Implants Provide Effective, Drug-Free Protection From Antibiotic-Resistant Bacteria and Fungus
(Photo: Wikimedia Commons/ Wellcome Library, London)

Infection can happen around implants like titanium hips or dental prostheses. For instance, hospital-acquired infections of medical devices occur in almost 10% of implants due to pathogenic Candida species. To avoid this problem, doctors use a range of antimicrobial coatings, antibiotics, and chemicals, but they fail to stop antibiotic-resistant strains and could even increase drug resistance.


Altered Titanium Surface

To solve this problem, scientists from the Royal Melbourne Institute of Technology (RMIT) designed a pattern of microscale spikes that can be sculpted onto titanium implants or other surfaces. It promises to offer effective protection against bacteria and fungus without using drugs.

The spikes were specially designed to resemble the size of a bacteria cell. The team tested its effectiveness in killing Candida, a deadly multi-drug resistant fungus responsible for one in everten10 hospital-acquired medical device infections.

After analyzing their effectiveness, the spike destroyed almost half of the bacteria cells soon after contact. The other half that did not immediately destroy were considered unviable from the sustained injuries and could not reproduce or cause bacterial infection.

The metabolic analysis of the protein activity of Candida albicans and multi-drug resistant Candida auris fungi cells revealed that they were as good as dead after having an injury on the surface. According to lead postdoctoral researcher Dr. Denver Linklater, the injured Candida cells suffered from extensive metabolic stress, which prevented them from reproducing to create a deadly fungal biofilm. These cells could not revive in a non-stress environment and finally shut down in a process called apoptosis or programmed cell death.

The research team hopes their findings can provide new insight into designing antifungal surfaces. This can help in preventing multi-drug resistant yeasts from forming dangerous biofilms.

READ ALSO: Novel Synthetic Antibiotic Designed To Overcome Antimicrobial Resistance Kills Pathogenic Superbugs


Antimicrobial Properties of Insect Wings

It was determined that insects can effectively fight bacteria and fungi using the special structure found in their wings. Insects have dull spikes called nanopillars, which are embedded in their wings. These structures, as big as bacteria, can kill pathogens by popping their cells.

Scientists believe this ability to resist microbial infestation is a unique feature developed over 400 million years of evolution in response to environmental and lifestyle pressures.

The nanostructured surfaces of ocicada Psaltoda claripennis wings canto mechanically kill pathogenic bacteria Pseudomonas aeruginosa and the drug-resistant Escherichia coli. The same ability is demonstrated by dragonfly Diplacoides bipunctata and damselfly Calopteryx haemorrhoidalis as they resist the infestation of Gram-positive, Gram-negative, and Bacillus subtilis spores.

RELATED ARTICLE: Scientists Discover Another Mechanism of Antimicrobial Resistance; How Serious Is This Threat?

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