London: Researchers have identified almost 2,000 unknown bacterial species in the human gut, a breakthrough that could help better understand human health and even guide the diagnosis and treatment of gastrointestinal diseases. The bacterial species discovered by researchers at the European Molecular Biology Laboratory and the Wellcome Sanger Institute in the United Kingdom have not yet been grown in the laboratory.
The team used a variety of computational methods to analyze samples from individuals around the world. The results, published in the journal Nature, show that although researchers may be closer to creating a complete list of common microbes in the microbiomes of the peoples of North America and Europe, there is a significant lack of data from other regions of the world. .
The human intestine is home to many species of microbes, collectively referred to as gut microbiota. Despite extensive studies in the field, researchers are still working on the identification of the individual microbial species that live in the gut and on the understanding of the roles they play in human health.
There are many reasons why some microbial species among the gut microbiota have remained unknown for so long, such as low abundance or an inability to survive outside. By using computational methods, the researchers were able to reconstruct the genomes of these bacteria.
“Computational methods allow us to understand the bacteria that we can not yet grow in the laboratory,” said Rob Finn of the European Molecular Biology Laboratory. “Using metagenomics to reconstruct bacterial genomes is like rebuilding hundreds of puzzles after mixing all the pieces,” not knowing what the final image should look like, and after completely removing some pieces of the mix just to make it a bit harder, “said Finn.
The research highlighted the composition of differences in intestinal bacteria among people around the world and the importance that the samples under study reflect this diversity.
“We are seeing that many of the same bacterial species arise in the data of the populations of Europe and North America,” said Finn. “However, the few data sets from South America and Africa that we had access to for this study revealed significant diversity that is not present in the previous populations,” he said.
“Computational methods allow us to get an idea of the many bacterial species that live in the human gut, how they evolved and what kind of roles they can play within their microbial community,” says Alexandre Almeida, a postdoctoral fellow at the Wellcome Sanger Institute.
In the study, the researchers took advantage of the most complete public databases of gastrointestinal bacteria to identify bacterial species that had not been seen before.
“Research like this is helping us create a so-called flat human bowel, which in the future could help us better understand human health and disease and could even guide the diagnosis and treatment of gastrointestinal diseases,” said Trevor Lawley, leader of the group. at the Wellcome Sanger Institute.