Researchers at the Wellcome Sanger Institute and EMBL’s European Bioinformatics Institute have identified over 140,000 viral species living in the human gut. Incredibly, over half of these have never been seen before.
Gut Health and Disease
The human gastrointestinal tract is an incredibly biodiverse environment. It is home to hundreds of thousands of viruses called bacteriophages, which can infect bacteria. These bacteriophages are able to drive evolutionary change within bacterial communities, by creating gene flow networks that fuel adaptation.
Furthermore, studies have shown that imbalances in our gut microbiome can contribute to diseases and complex conditions, such as inflammatory bowel disease, allergies and obesity. However, the role of our bacteria and the bacteriophages which infect is largely unknown. As is the extent of viral diversity and its prevalence in the human gut.
The Gut Phage Database (GPD)
A recent study created the GPD, a collection of ~142,000 viral genomes. These were obtained through mining a dataset of 28,000 human gut metagenomes from across the world, and almost 3000 reference genomes of cultured gut bacteria.
Dr Alexandre Almeida, a key member of the study stressed we must remember that not all viruses are harmful. In many cases, they are an integral component of the gut ecosystem. The viral samples analysed were taken from mainly healthy individuals who didn’t share any specific diseases. Furthermore, many of these viruses have DNA as their genetic material. These differ from well known pathogens such as SARS-CoV-2 or Zika, which are RNA viruses.
Another key discovery was the presence of a highly prevalent group of viruses in the gut. These were believed to all have a common ancestor. The authors refer to these as the Gubaphage and was the second most prevalent virus clade in the human gut.
A High Quality Resource
The researchers used a stringent quality control pipeline, coupled with a machine-learning approach to avoid any contamination and obtain highly complete viral genomes. These high quality genomes will help pave the way to a better understanding of the roles viruses play in our gut microbiome.
The goal is to use this information to discover new treatments, such as antimicrobials from bacteriophage origin. The GPD will be an invaluable resource for those studying bacteriophages and their role in human health.
The number and diversity of viruses found in this study was surprisingly high. This data opens up new research avenues for understanding how viruses living in the gastrointestinal tract impact human health.
Image Credit: By kjpargeter – freepik