Tiny creatures inherit genes from bacteria capable of producing antibiotics

A group of small, freshwater animals known as bdelloid rotifers have been found to protect themselves from infections by utilizing antibiotic recipes „stolen“ from bacteria, according to a recent study published in the journal Nature Communications. These tiny creatures, with the name bdelloid meaning ‚crawling wheel-animals‘, possess all the typical features of animals such as a head, mouth, gut, muscles, and nerves, despite being smaller than a hair’s breadth.

When exposed to fungal infections, the study revealed that rotifers activate hundreds of genes that they have acquired from bacteria and other microbes. Some of these genes are responsible for producing resistance weapons like antibiotics and other antimicrobial agents within the rotifers. This discovery marks the first instance of rotifers utilizing these acquired genes to combat diseases, distinguishing them from other animals that do not exhibit such behavior.

Previous research has shown that rotifers have been incorporating DNA from their environment for millions of years, but this study sheds light on their ability to use these genes in defense against pathogens. The genes acquired from bacteria have evolved within rotifers, leading to the production of complex antimicrobial compounds that may potentially be less toxic to animals, including humans, compared to traditional antibiotics derived from bacteria and fungi.

According to coauthor David Mark Welch, a senior scientist and director of the Josephine Bay Paul Center at the Marine Biological Laboratory, the genes acquired by rotifers are unique and not found in other animals. This suggests that rotifers may be producing novel antimicrobials that could offer valuable insights for the development of safer and more effective drugs to treat infections caused by bacteria and fungi in humans.

The study found that when exposed to a fungal pathogen, rotifers with horizontally acquired genes were more likely to upregulate these genes compared to other genes. Among the upregulated genes, clusters resembling bacterial polyketide and nonribosomal peptide synthetases responsible for producing antibiotics were significantly overrepresented. In fact, the upregulation of these clusters in a pathogen-resistant rotifer species was nearly ten times stronger than in a susceptible species.

Most antibiotics found in nature are produced by fungi and bacteria, and humans have been able to create synthetic versions for medicinal use. The discovery that rotifers may be producing similar chemicals within their cells suggests that they could hold the key to developing safer and more effective drugs for treating infections in humans and other animals.

One of the challenges in drug development is the toxicity and side effects associated with many antibiotic compounds derived from bacteria and fungi. By studying how rotifers naturally produce antimicrobial agents, researchers may uncover new avenues for drug discovery that are safer and more efficient in combating harmful microbes in the human body. The unique ability of rotifers to utilize genes acquired from bacteria highlights their potential as a valuable resource in the search for novel treatments for infectious diseases.