AFM helps unravel secrets of the gut
19 Apr 2013
A technique based on atomic force microscopy has been developed to help read information encoded in the gut lining.
Scientists from the Institute of Food Research (IFR) have adapted an atomic force microscopy (AFM) technique to understand the role of mucus in maintaining a healthy gut.
AFM works by running a very fine stylus mounted on the end of a flexible cantilever over the surface of a molecule.
The mucin molecules are immersed in saline, and float like a sea of kelp
A laser is bounced off the cantilever, amplifying the signal so that AFM can detect distances down to a millionth the width of a sheet of paper.
Patrick Gunning and Andrew Kirby, from IFR’s AFM group, adapted this technique by attaching sugar-binding molecules called lectins to the AFM cantilever, via a flexible linker. They used this to probe mucins bound to a surface.
“It’s a bit like fishing” said Dr Gunning. “The mucin molecules are immersed in saline, and float like a sea of kelp. We use lectins as the bait. We drop the line down until we hit the bottom, and then lift it back up. If the lectin finds a target sugar molecule on the mucin, it snags.”
Measuring the distance between the snags gives a picture of what the overall mucin molecule looks like.
By repeating this thousands of times, and then working with IFR’s biomathematicians, it was possible to produce a ’fingerprint’ that characterise different mucins.
The team could then differentiate between mucins derived from different parts of the gut.
The researchers now want to look at the mucins derived from diseased tissues, to further investigate differences in the glycocode.
