An international team led by Nobel laureate Andrew Fire has identified a novel biological entity in oral and intestinal bacteria, termed 'Obelisco'. This infectious agent possesses a simple genome and its health implications remain largely unknown.
The discovery, involving the Institute of Molecular and Cellular Biology of Plants (IBMCP) and the Spanish National Research Council (CSIC), was published in the journal Cell. The research utilized bioinformatics to analyze genetic sequences from human fecal samples, revealing the presence of Obeliscos in 7% of the 440 subjects examined.
These agents, characterized by a circular RNA genome of approximately 1,000 nucleotides, challenge existing classifications of life forms. They share similarities with viroids, subviral agents that infect plants, yet have distinct properties.
Notably, a strain of Streptococcus sanguinis, a common oral bacterium, was found to accumulate Obeliscos significantly, suggesting a potential link between these entities and oral health.
The implications of this discovery extend to understanding microbial diversity and evolution, as well as potential health impacts, as the microbiome plays a crucial role in various physiological functions.