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Antibiotic resistance is a growing concern throughout the world. A recent study investigates whether blue light can destroy these ‘superbugs.’
Antibiotic resistance is on the rise, globally; this means that antibiotics that once treated certain infections no longer have any effect.
In an effort to combat this ever-growing concern, researchers are looking for answers in unlikely places, including the bacteria that live on insects, and the slimy coats of fish.
Other researchers are investigating whether combinations of existing antibiotics might be more effective against certain superbugs.
Some scientists are looking to innovative technologies, striving to find alternative methods to destroy these increasingly deadly pathogens.
Recently, scientists from Purdue University in West Lafayette, IN, and Boston University in Massachusetts investigated the potential power of blue light.
The scientists focused their research on, arguably, the most well-known strain of antibiotic-resistant bacteria — methicillin-resistant Staphylococcus aureus (MRSA).
Doctors can treat most of these infections successfully, but severe MRSA infections can result in amputation or even death.
S. aureus, along with other strains of bacteria, produces pigments that play a role in protecting the bacteria from attack.
Scientists have found that S. aureuscontains a golden pigment called staphyloxanthin (STX) that protects it against neutrophils — a type of white blood cell that plays a pivotal role in the fight against pathogens.
A process called photobleaching can reduce levels of this pigment. This weakens the bacterium’s membrane, which makes it easier to kill; this limits the amount of damage that the bacteria can cause.
Some researchers have already looked for ways to knock out STX using medication. One study, for instance, looked at an existing antifungal drug. However, drug-based approaches have not, so far, yielded improved treatments for antibiotic-resistant infections. Finding a way to remove STX’s teeth without drugs might provide a new approach to these difficult-to-treat pathogens.
The scientists found, accidentally, that if they photobleached MRSA using blue light, they could break down STX. The photobleaching caused their membrane to become more permeable, rendering the bacteria defenseless.
After photobleaching, the bacteria were susceptible to even relatively mild antiseptics, such as hydrogen peroxide.
They tested the blue light approach in a range of scenarios, including cultured bacteria, MRSA-infected immune cells, biofilms of S. aureus, and two models of wound infection in mice.