The most prevalent gastrointestinal condition, Irritable Bowel Syndrome (IBS), is determined primarily on the basis of symptoms. The IBS has been linked to the changes in the bacterial component of the gut microbiome (the bacteriome) but in spite of the virome’s recognized function (especially bacteriophages), in molding the gut bacteriome, few researchers have looked at the virome in IBS. To examine fecal Virus-Like Particles (VLPs) from 55 IBS patients and 51 healthy people, metagenomic sequencing was used by the researchers. The researchers found a significant difference in beta diversity and reduced alpha diversity of viral clusters containing both known and unknown viruses (viral ‘dark matter’) in IBS compared to controls, but not within IBS symptom subtypes. The Siphoviridae, Myoviridae, and Podoviridae families were the three most ample bacteriophage clusters (Order Caudovirales). In IBS and control participants, a core virome (defined as a cluster present in at least 50% of samples) comprising 5 and 12 viral clusters was found, respectively. Demonstrating differential abundance between IBS and controls, a subgroup of viral clusters was also discovered. There were no significant correlations between the virome and the bacteriome, IBS clinical subtype, or the presence of bile acid malabsorption. Differences in the virome, on the other hand, could be traced back to the bacteriome, as CRISPR spacer analysis revealed that virome changes were at least largely related to bacteriome changes. No evidence was found of core viral clusters shifting from lytic to lysogenic replication, which has been observed in the gut virome of individuals with Inflammatory Bowel Disease (IBD). The study revealed that people with IBS have altered viromes, notwithstanding the clinical subtype, which could help with the development of new microbiome-based treatments.
Link:www.tandfonline.com/doi/full/10.1080/19490976.2021.1887719
