Our gut hosts a community of trillions
of microbes, called the gut microbiota, and we are becoming increasingly aware
that this has significant effects on many aspects of our health. However, the
molecular mechanisms underpinning this interaction remain elusive.
New research led by Dr Nathalie Juge at
the Quadram Institute has identified some of the molecules used to ensure
bacteria in the gut microbiota maintain healthy populations, in the correct
locations in the body. This helps to ensure a continuing mutually beneficial
relationship with our gut microbiota.
To achieve a friendly relationship with
these microbes, our gut is lined with mucus. In the colon, the mucus layer is
divided into a loose outer layer that provides a suitable habitat for bacteria,
allowing us to benefit from them, and an inner layer that acts as a protective
barrier. This inner layer prevents these bacteria crossing the gut lining where
they could cause us harm.
Mucus is made up of large protein
molecules, which are decorated and extended by different sugar molecules,
called oligosaccharides that together with water make up mucus. These mucin
glycan chains provide a source of nutrients as well as an attachment site for
bacteria that have evolved to colonise the outer mucus layer. Over 100
different oligosaccharides have been identified in the human colon, and recent
research has shown that variations in the oligosaccharides within the mucus are
associated with variations in the composition of the gut microbiota. This may
be one way in which the body tries to tailor the composition of the microbiota in
different parts of the gastrointestinal tract.
See:
Posted by Dr. Tim Sandle
