Microbial species that live in the gut and understand what roles they play in human health Photo: Getty Images
London: Researchers have identified nearly 2,000 types of unknown bacteria in human intestines, progress that can help understand human health better and even guide the diagnosis and treatment of gastrointestinal diseases. The bacterial species discovered by researchers in the European Molecular Biology Laboratory and the Volck Sanger Institute in the UK are still not cultured in the laboratory.
The team used a variety of computational methods to analyze samples of people around the world. The results, published in the journal Nature, show that although researchers may be approaching a comprehensive list of bacteria common to microbiomes of people from North America and Europe, there is a significant lack of data from other regions of the world.
Human intestines are home to many species of bacteria, collectively called gut microbiota. Despite extensive studies in the field, researchers are still working on identifying individual bacterial species living in the intestines and understanding what roles are in human health.
There are many reasons that some microbial species between microbiota and intestines have remained known for so long, such as low abundance or inability to survive outside of it. Using computational methods, the researchers were able to reconstruct the genome of these bacteria.
"Computational methods allow us to understand microbes that we can not yet contribute to the laboratory," said Rob Payne of the European Molecular Biology Laboratory. "The use of metagenomics to reconstruct the bacterial genome is a bit like restoring hundreds of puzzles after mixing all the pieces together, without knowing what the final image should look like, and after completely removing some pieces from the mix just to make it a bit harder," Finn said.
The study highlighted the composition of intestinal bacterial differences between people around the world, and how important it is for the samples under research to reflect this diversity.
"The data for European and North American populations were many, but according to the few data from South America and Africa to which we had access to this study, significant diversity was not found in the former populations," he said.
"Computational methods allow us to get an idea of the many microbes that live in the human gut, how they evolved and what roles they can play within their microbial community," says Alexander Almeida, a postdoctoral fellow at the Volcam Sanger Institute.
In the study, the researchers appointed the most comprehensive public databases of gastrointestinal bacteria to identify previously unknown bacterial species.
"Such research helps us create a so-called master plan for the human intestines, which in the future can help us better understand human health and disease and can even guide the diagnosis and treatment of gastrointestinal diseases," said Trevor Loli at the Volks Sanger Institute.