How Does Copper Interact with Staph aureus?

Jeff Boyd, PhD, assistant professor of Biochemistry and Microbiology at Rutgers School of Environmental and Biological Sciences, explains how copper can be used to prevent a Staphylococcus aureus infection.

Interview Transcript (slightly modified for readability).

“Copper is something that we’re interested in in my lab and I think it’s a very interesting molecule to actually prevent or to treat [Staphylococcus] aureus infections. I should say prevent; people really don’t use copper to treat Staph aureus infections. But it’s something that’s been around for thousands of years. People have been carrying water in copper jugs for thousands of years and it’s the advent of antimicrobial resistance, not just Staph aureus resistance. But antimicrobial resistance has led us to, as scientists, as physicians, as healthcare professionals, look at other avenues which we might want to pursue to prevent these types of infections. Things like personal hygiene, washing your hands after you’ve seen a patient, sterilizing your hands after you see a patient, [and] other things, such as maybe coating a surface on a bedrail or on a call button with an antimicrobial compound [can help prevent infections with these bacteria].

One such compound is copper; this is a naturally-occurring mineral. It is relatively expensive, but it’s also very effective at killing microbes; it can kill bacteria, it can kill viruses, and in some instances, it’s been at least purposed to be able to kill spores, such as C. diff or Clostridium Difficile type spores.

So, how [does] copper interacts with the organism? Copper is a positively charged ion and what copper can do is actually bind to the outside of the cell, something that might have a negatively charged residue on it. Copper can then disrupt the membrane. Remember before we were talking about how organisms use oxygen to breathe, just like we do [and] microbes do? Copper has the ability to disrupt a membrane and then they can’t effectively use oxygen to breathe any longer, so now they’re going to grow a lot slower. It puts holes in their cell membranes and allows cellular components to leak out, as well as to leak in.

Ultimately, it can also accumulate in the cytosol and react with oxygen or other molecules to lead to what’s called reactive oxygen species and reactive oxygen species can lead to protein damage, lipid damage, DNA damage, and ultimately, if allowed to accumulate or to raise to a high enough concentration, cell death.

I should also point out that it’s quite interesting that not only humans have been using, not only reactive oxygen species and copper for thousands of years to treat or to prevent infections by microbes, but our human body actually uses copper as an antimicrobial as well. Phagosomes in white blood cells will accumulate copper when they engulf a microbe and that copper aids in killing that microbe, so our bodies use copper to aid in clearing microbial infections."