A gold pill could be our superbug secret weapon

There’s no underselling the role antibiotics has had on our lives; when widespread use of penicillin ushered in the ‘golden age’ of antibiotics after World War II, and discovery of many new antibiotics, the infectious diseases that used to be massive killers seemed a thing of the past. Prior to the 20th century, the average life expectancy in the US was 47. As of 2021, it was 76.4.

However, given that bacteria is the oldest form of life on earth, it’s no surprise it’s been able to fight back. Helping this is its dazzling ability to reproduce, meaning that any microbes that evolve to be resistant to drugs can quickly dominate a population, rendering the antibiotic ineffective.

The latest promising research on fighting these stubborn, smart superbugs is, quite simply, gold. Presenting their novel research in Copenhagen this week, researchers from the Barcelona Institute for Global Health found very promising results when they lined up 19 gold compounds against several types of multidrug-resistant bacteria isolated from patients.

With its antibacterial properties, it’s not the first time the precious mineral has been touted as a potential life-saver, with research into gold nanoparticles on their own, and also combined with infrared light treatments, to fight off infections.

Metalloantibiotics – compounds with a gold ion at their core – has the potential to kill bacteria and prevent its adaptation to form resistance.

“Gold complexes use a variety of techniques to kill bacteria,” said Sara Soto Gonzalez of the Barcelona institute. “They stop enzymes from working, disrupt the function of the bacterial membrane and damage DNA.”

The team tested the gold compounds against bugs including Methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis, Pseudomonas aeruginosa; Stenotrophomonas maltophilia, Acinetobacter baumannii and bacterial pneumonia.

There was evidence of high efficacy against MRSA and S. epidermis in 16 of the 19 compounds, and 16 were effective in fighting gram-negative bacteria – the types with the greatest resistance to current antibiotics.

“It is particularly exciting to see that some of the gold complexes were effective against MRSA and multidrug-resistant A. baumannii, as [these are the} two biggest causes of hospital-acquired infections,” Soto Gonzalez said. “With research on other types of gold metalloantibiotics also providing promising results, the future is bright for gold-based antibiotics.”

While in a preliminary study stage, the researchers point out that development of this kind of antibiotic would be neither expensive nor difficult.

“The type of gold complexes we studied, known as gold (III) complexes, are relatively straightforward and inexpensive to make,” Soto Gonzalez added. “They can also be easily modified and so provide a vast amount of scope for drug development.”

The new research paper will be presented at the European Congress of Clinical Microbiology and Infectious Diseases in Copenhagen between April 15-18.

Source: European Congress of Clinical Microbiology and Infectious Diseases