Researchers have discovered a promising solution to the growing threat of antimicrobial resistance (AMR) – dietary zinc supplements. This study, published in Applied and Environmental Microbiology, reveals how zinc can inhibit the transmission of AMR genes between microbes, potentially slowing the spread of drug-resistant infections. With millions of people affected by AMR infections annually, this finding offers a cost-effective and accessible approach to addressing this global health challenge.
Zinc’s Surprising Role
A team of scientists, including microbiologist Melha Mellata, Ph. D., and fellow researchers at Iowa State University, have found an amazing new function of dietary zinc: It can interfere with the transfer of antimicrobial resistance genes between bacteria.
The rapid spread of AMR genes is facilitated by plasmids, which are circular genetic DNA constituents. One such way is with plasmids — small, circular pieces of DNA that can jump from one bacterium to another (lateral transfer, usually within the gut). Mellata and her group identified that providing bacterial strains with an extra dose of zinc greatly curbed the spread of these AMR-carrying plasmids.
‘ This is the first example where we have found that, at lower concentrations with minimal effects on bacteria, zinc inhibits plasmid transfer. This finding is particularly important as perturbation of the gut microbiome by prolonged antibiotic treatment can have deleterious effects on human health. The researchers hope to slow the spread of AMR by interfering with the plasmid transfer process while maintaining homeostasis within the gut ecosystem.
Understanding the Mechanisms
The scientists then investigated further to see how zinc could inhibit the transfer of plasmids. They showed by qPCR analysis that zinc caused the overexpression of replication genes, which could have overloaded and interrupted the plasmid transfer as a whole.
Although zinc appeared to turn on the genes involved in conjugation (plasmid transfer), it also turned off the specific proteins that help build the structures to deliver plasmids from one bacterium to another. Consequently, the complete process of plasmid conjugation was significantly inhibited.
The leader of the study, Logan Ott, said; “Some of these mechanisms are not exactly the ones that you would expect based on what previous literature would suggest you might see with a metal like zinc inducing this inhibition. This will both reinforce existing knowledge on how bacteria interact as well as exchange their genes in the gut, while also opening new lanes of research.
Promising Next Steps
This new, inexpensive and commonly available treatment approach has the researchers particularly excited about its potential to fight increasing AMR. The next stages involve testing the transfer of plasmids, dogged with other AMR genes and animal infection models to ascertain if the lab represents what occurs in animals.
“Sometimes the answer might be to just use the old stuff that we already have in our closet,” Mellata said, highlighting how more work is needed on known compounds such as zinc to fight new health threats.
While the world battles a frightening increase in AMR infections that kill 35,000 people annually in America alone, these findings introduce an upbeat note. Just as this common mineral zinc You be in a position of introducing to your toolbox in the scientific kit bag, offers a new, inexpensive way that shows promise for halting Antimicrobial resistance (AMR), and hence save millions of life globally.
