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Our gut bacteria ‘talk’ to our very own body cells! This discovery is hoped to pave the way to elaborating treatment procedures for certain metabolic disorders. The new findings are published in the journal Nature.
A Conversation Between Humans & Bacteria
We co-exist with our gut bacteria, bound by a mutually beneficial relationship. We need them as they need us—they feed on some of our food while helping us to digest it. How do these interactions work? According to the new study conducted by researchers from The Rockefeller University and the Icahn School of Medicine at Mt. Sinai, these bacteria and our body cells speak the same chemical language. The team now wishes to use this human-bacteria understanding to genetically engineer gut microbiota to produce molecules that can potentially be used for treatment purposes.
Communication Molecule: The Ligand
The common language ‘spoken’ by the two types of cells is based on molecules known as ligands, says the scientist who made the discovery, Sean Brady, the director of Rockefeller University’s Laboratory of Genetically Encoded Small Molecules. Ligands (in humans) will normally bind with receptors located on the membranes of human cells to generate specific biological effects, a process being copied by the bacteria.
Making Bacteria More Human
Brady and his colleagues changed gut bacteria obtained from humans to make microbial molecules. These bacteria-derived substances were found to be mimicking specific human ligands known to adhere to receptors called GPCRs (G-protein-coupled receptors), which happen to be the most common targets for drugs because of their involvement in metabolic diseases.
“If you‘re going to talk to bacteria,” says Brady, “you’re going to talk to them right there.”
The ‘human-ligand-clones’ are N-acyl amides which bind specifically to GPR 119, a receptor that plays a role in the regulation of glucose and appetite. When they were tested in mice, it was found that their introduction into the latter’s system led to decreased blood glucose levels, among other metabolic changes. This is why the researchers think that the bacterial molecules may be used to treat disorders linked with human metabolism.
Bacteria Are Part of Us
But, can we really use molecules coming from bacteria to treat diseases? Wouldn’t they be harmful?
Brady explains that the ‘bacterial ligands’ are not considered to be foreign even if they come from non-human microorganisms, because the microbes are part and parcel of human physiology. The team is simply manipulating a natural system.
This research constitutes only the first step in this field of study. The subsequent phases will delve into the chemistry being used by the microbes to interact with humans.
“This is a first step in what we hope is a larger-scale, functional interrogation of what the molecules derived from microbes can do,” Brady says.