Feb. 12 (UPI) -- Scientists at the European Molecular Biology Laboratory have identified nearly 2,000 previously unknown bacterial species living in the human gut.
Researchers with the lab's European Bioinformatics Institute collected gut cultures from study participants around the world. The microbiologists used a variety of computational methods to sequence the genes found in the samples.
Studies show the communities of microbes living inside the intestines play a vital role in human health. Dozens of maladies have been linked to imbalances within the gut microbiome. Research even suggests gut bacteria influences gene expression.
Despite increasing numbers of microbiome studies, scientists' understanding of the communities of microorganisms occupying the human gut -- the gut microbiota -- remains incomplete.
To better understand which gut microbes are shared by humans and why they thrive inside human intestines, scientists are developing new ways to efficiently sequence the genomes of gut microbiota.
"Computational methods allow us to understand bacteria that we cannot yet culture in the lab," Rob Finn, researcher at the European Bioinformatics Institute, said in a news release. "Using metagenomics to reconstruct bacterial genomes is a bit like reconstructing hundreds of puzzles after mixing all the pieces together, without knowing what the final image is meant to look like, and after completely removing a few pieces from the mix just to make it that bit harder."
"Researchers are now at a stage where they can use a range of computational tools to complement and sometimes guide lab work, in order to uncover new insights into the human gut," Finn said.
In addition to finding commonalities among human gut microbiota, new sequencing techniques are revealing unique geographical differences among the microbial communities found in the guts of disparate populations. The microbiome inside the human gut evolves in response to a person's diet and environment.
"We are seeing a lot of the same bacterial species crop up in the data from European and North American populations," Finn said. "However, the few South American and African datasets we had access to for this study revealed significant diversity not present in the former populations. This suggests that collecting data from underrepresented populations is essential if we want to achieve a truly comprehensive picture of the composition of the human gut."
According to the researchers, the techniques used to mine public databases of gastrointestinal bacteria for new species can be easily reproduced for future studies. Scientists detailed their efforts in the journal Nature.
"Research such as this is helping us create a so-called blueprint of the human gut, which in the future could help us understand human health and disease better and could even guide diagnosis and treatment of gastrointestinal diseases," said Trevor Lawley, researcher at the Wellcome Sanger Institute.
