The secret of the evolution of the intestinal flora

B. Fragilis phase variable type I RM system. (A) Regional genetic map. hsdR – Restriction enzyme. The colored region of hsdM-methylase; BF9343_1757-60 represents the phase variable inversion region of hsdS (specific gene). (B) A gene region showing a specific gene. i-iv shows the different DNA reverse directions that can occur in this region between the reverse repeats shown by the dashed lines. Only the outlined genes are transcribed. (C) A combination of eight specific genes possible from different DNA inversions. (D) EtBr-stained agarose gel of amplicon that detects each of the six specific half genes at the expressed locus. Each fragment was amplified using primer F1 paired with each of the six reverse primers.

How does our gut react and adapt to changing situations? Where does this basic and important flexibility come from? Technion scientists say the gut flora Through the microbiota, we are elucidating the genius of the intestine, including gene reversal.

Assistant Professor Naama Geva-Zatorsky of Rappaport School of Medicine and PhD student Nadav Ben-Assa, in collaboration with scientists at Harvard University, Gut microbiota Respond to habitat changes. Their findings are Nucleic acid research, A peer-reviewed scientific journal at Oxford University Press.

Is Human microbiota It refers to a collection of microorganisms (bacteria, viruses, etc.) that settle on the inner and outer surfaces of the human body.The most abundant and diverse in the human intestine Microbiota population.

The gut microbiota provides a basic coping mechanism within the dynamic environment of the gut, where structural, mechanical, and chemical changes occur constantly. One of the mechanisms that helps the gut microbiota work is the rapid and reversible changes in the genome in response to external stimuli.

Article published in Nucleic acid research Describes this mechanism in Bacteroides fragilis, one of the most abundant bacterial species in the human gut. This bacterium can invert a large number of regions defined throughout the genomic sequence. Researchers have focused on the relationship between this ability and gene expression in living organisms.

When the research team examined the gene expression of these changes (recombination), they found extensive changes in the bacterial genome.

“In particular, we discovered changes in the sugars that surround the bacteria,” said Professor Geva-Zatorsky. “These sugars act as a kind of” identification card “that helps bacteria communicate with the environment. These sugars help our body, or more precisely, our body. Immune system, Identify the type of bacteria present and respond accordingly. This is why we assume that changes in the gut change that “ID card”. Bacteria In different ways. “

Researchers emphasized that these are reversible gene reversals based on recombination of regions within the genome in the major systems of B. fragilis organisms. Therefore, this recombination has a wide range of effects on the gene expression of organisms, including various biomolecules.

Genetic analysis was performed using SMRT (single molecule real-time) sequencing, an innovative technology from Pacific Biosciences (PacBio) developed over the last decade. This technique enables long-range sequencing and mapping of DNA molecules and detection of epigenetic DNA modifications. In the system studied, gene recombination affected gene modification and, as a result, affected gene expression throughout B. fragilis. The system can also detect hostile elements such as bacteriophage. This is the subject of new research currently underway in the laboratory.

Plant and Microbial Homeostasis: A Delicate Balancing Act

For more information:
Nadav Ben-Assa et al, Analysis of Phase Variable Restriction Modification System of Bacteroides fragilis, a human gut symbiotic organism, Nucleic acid research (2020). DOI: 10.1093 / nar / gkaa824

Quote: Evolutionary Secrets of the Gut Microbiota Obtained from on June 11, 2021 (June 11, 2021)

This document is subject to copyright. No part may be reproduced without written permission, except for private research or fair trade for research purposes. The content is provided for informational purposes only.

The secret of the evolution of the intestinal flora

Source link The secret of the evolution of the intestinal flora

Related Articles

Back to top button