Each year, more than 23,000 people in the United States die as a result of infections that are resistant to current antibiotics, highlighting the desperate need to develop new antimicrobial medications. A new study reveals how the blood of the Komodo dragon could help to achieve this goal.
Study co-author Monique van Hoek, of the School of Systems Biology at George Mason University in Manassas, VA, and team recently published their findings in the journal NPJ Biofilms and Microbiomes.
Antibiotic resistance – whereby harmful microbes have developed resistance to drugs that once killed them – has become one of today’s biggest threats to public health.
According to the Centers for Disease Control and Prevention (CDC), every year, at least 2 million people in the U.S. become infected with drug-resistant bacteria, and at least 23,000 deaths occur as a direct result.
The bacterium Clostridium difficile is one of the biggest threats, responsible for around 250,000 infections and 14,000 deaths annually.
While the overuse and incorrect use of antibiotics are key drivers of resistance, the fact that no new antibiotics have been developed over the past 30 years has not helped; relying on the same medications for so long has provided microbes with the opportunity to evolve and escape the clutches of drugs that once destroyed them.
With the World Health Organization (WHO) warning that we are on the cusp of entering a “post-antibiotic era,” the race is on to find new antibiotics that can combat drug-resistant infections.
The new study from van Hoek and colleagues turned to Komodo dragons as a possible source.
The Komodo dragon is a lizard that can be found on five islands in Indonesia: Komodo, Rinca, Flores, Gili Motang, and Padar.
It is the world’s largest living species of lizard, capable of growing up to 10 feet in length. However, that is not the only characteristic that makes it unique. According to van Hoek and team, the reptile rarely becomes ill, despite eating decaying flesh and possessing saliva that is rich in harmful bacteria.
The researchers say that this is down to a peptide found in their blood called VK25, which they isolated from a Komodo dragon residing at the St. Augustine Alligator Farm Zoological Park in Florida.
On closely analyzing this peptide, the team found that it possessed mild antimicrobial properties and had the ability to prevent biofilms, which are microorganisms that stick together in order to thrive and protect themselves. These are often found in wounds.
The researchers rearranged two amino acids present in VK25 with the aim of making it more effective. This led to the development of a new, synthetic version of the peptide, which they named DRGN-1.
“The synthesized peptide DRGN-1 is not a Komodo dragon’s natural peptide; it’s been altered to be stronger in terms of both potency and stability,” notes van Hoek.
Next, the team tested DRGN-1 on mice with wounds that were infected with two strains of antibiotic-resistant bacteria: Pseudomonas aeruginosa and Staphylococcus aureus.
The synthetic peptide attacked and destroyed the biofilm of the wounds, before killing the two bacterial strains. This led to a faster wound-healing process.
The researchers now plan to test the potential of DRGN-1 as a topical, wound-healing product for animals, but they are hopeful that the peptide could lead to new antibiotics for human use.
“Synthetic germ-fighter peptides are a new approach to potentially defeat bacteria that have grown resistant to conventional antibiotics. The antimicrobial peptides we’re tapping into represent millions of years of evolution in protecting immune systems from dangerous infections.”
Monique van Hoek