OCT 08, 2021 9:14 AM PDT

'Living Medicines' to Destroy Dangerous Biofilms

WRITTEN BY: Carmen Leitch

Bacteria that grow in colonies can be extremely difficult to eliminate; the bacteria in these groups often become resistant to drugs or antimicrobials. Known as biofilms, bacterial communities that grow on surfaces can be found in many places, including medical devices. Biofilms are far stronger than free-floating microbes on their own, and an estimated 80 percent of chronic infections are linked to biofilms. Scientists have now devised a new approach to attack these dangerous bugs, with a 'living medicine' that's made up of other microbes.

A digitally colorized SEM image of mustard-colored methicillin-resistant, Staphylococcus aureus (MRSA) bacteria, enmeshed in a red-colored human white blood cell. / Credit: National Institute of Allergy and Infectious Diseases (NIAID)

The medicine was tested on catheters that were infected with biofilms in three settings: in the lab, in tissue taken from an organism, and in a mouse model. When the mouse model of infection was treated with the 'living medicine,' 82 percent of infections were eliminated. The findings have been reported in Molecular Systems Biology.

Many biofilms are caused by Staphylococcus aureus, and standard antibiotics cannot remove them. So if a patient has a medical implant infected by an S. aureus biofilm, enzymes or antibodies are sometimes useful, but these treatments can harm normal cells and cause side effects because they are not designed to specifically target the infection. Patients may have to undergo surgery to remove the infection.

Microbes are already engaged in a battle with one another for resources and survival. The researchers thought that the molecules produced by living microorganisms could be another way to treat biofilms. Bacterial genomes are also small and easily manipulated. In this study, the scientists selected a bacterium called Mycoplasma pneumoniae, which doesn't have a cell wall. As such, it can evade the immune system and can easily release therapeutic molecules. This microbe also tends to hold onto its DNA, which doesn't tend to mutate naturally, and not pass it to other microbes.

The researchers began by eliminating the pathogenicity of this bacterium so it would not make people sick. They also engineered the bacterial genome to easily release two enzymes that it was modified to produce. Each of those enzymes can dissolve biofilms.

The scientists are hopeful that these bacteria can be used first to remove biofilms from breathing tubes. Safety testing is complete. The next issue to address is manufacturing, "and we expect to start clinical trials in 2023," said co-corresponding study author María Lluch, Chief Science Officer of Pulmobiotics S.L.

This technique might be applicable to other health problems."Bacteria are ideal vehicles for 'living medicine' because they can carry any given therapeutic protein to treat the source of a disease," suggested study co-author Luis Serrano, ICREA Research Professor and Director of the Centre for Genomic Regulation. "One of the great benefits of the technology is that once they reach their destination, bacterial vectors offer continuous and localized production of the therapeutic molecule."

Sources: Centre for Genomic Regulation, Molecular Systems Biology

 

About the Author
  • Experienced research scientist and technical expert with authorships on over 30 peer-reviewed publications, traveler to over 70 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
SEP 13, 2021
Health & Medicine
How Farming Shaped the Immune System
SEP 13, 2021
How Farming Shaped the Immune System
In today's society, a rural upbringing is associated with a healthier immune system less prone to allergies and auto ...
SEP 14, 2021
Technology
Dental Implant Produces Its Own Electricity And Fights Bacteria
SEP 14, 2021
Dental Implant Produces Its Own Electricity And Fights Bacteria
The use of dental implants offers a long term, effective treatment approach for lost or missing teeth compared to method ...
SEP 14, 2021
Microbiology
Learn How Good Bugs Can Benefit Us at International Microorganism Day
SEP 14, 2021
Learn How Good Bugs Can Benefit Us at International Microorganism Day
Microorganisms live everywhere, and we've learned over the past year that they can affect everything.
SEP 30, 2021
Cancer
Gut Microbiota Influences Colon Cancer Development
SEP 30, 2021
Gut Microbiota Influences Colon Cancer Development
The gut microbiome consists of all the microorganisms living in an individual’s digestive system. Various factors ...
SEP 27, 2021
Microbiology
Rift Valley Fever's Infectious Secret is Revealed
SEP 27, 2021
Rift Valley Fever's Infectious Secret is Revealed
Rift Valley fever virus is carried by mosquitoes, and when it's passed to livestock including cattle, goats, and sheep, ...
NOV 09, 2021
Earth & The Environment
Ancient Egyptian Bees in Danger
NOV 09, 2021
Ancient Egyptian Bees in Danger
Honeybees have a long history in Egypt. Ancient Egyptians harvested honey from wild bees thousands of years ago, and bee ...
Loading Comments...