Behind the picture: New microscope tech that’s as good as gold
Christmas decoration? Modern art? Anything to do with science at all? Of course it is. As well as being pretty to look at, this little grid full of holes could have a big impact on microscopy. Dr Chris Russo, a researcher at the MRC Laboratory of Molecular Biology (MRC LMB) and the person who took the photo, explains more.
It might look like something you should hang on your wall, but this picture is actually a close-up of a tiny gold device that could allow researchers to unravel the details of how the complex biological machines inside cells work.
Working with Dr Lori Passmore, I have used this ‘grid’, which costs just a few pounds to make, to almost double the image quality of a multi-million pound electron microscope.
We then used it to determine the structure of a protein called ferritin, a small protein cage which stores the iron that cells need to function, and a particularly tough structure to determine.
Scientists often study the structure of biological specimens, such as proteins, by taking pictures of them with high-resolution electron microscopes. The proteins are frozen in ice and held steady inside the microscope on support structures called grids while the electrons pass through the specimen to the microscope’s camera.
Unfortunately, both the specimen and the grid tend to move around while the images are taken, leading to blurry pictures. Using a new generation of high-speed electron microscope camera (developed in part at the LMB), we recorded videos of a specimen during imaging to understand more about where the movement comes from.
Armed with this knowledge, we designed this new grid, made entirely of gold, which moves around 50 times less in the vertical direction and half as much in the horizontal direction while an image is taken.
The image shows a magnified view of one section of a new grid. It is a thin, round disk made entirely out of gold. The disk itself is a metal mesh (the squares in the image) that holds a thin film of gold that is full of tiny holes. Each hole is around 100 times smaller than a human hair in diameter, and just the right size to contain the protein machines responsible for life.
We’re hoping that the improvement in image quality afforded by these new grids will allow scientists to study many important proteins that were previously too difficult for current microscopes.
The research is published today in the journal Science. (Science, doi 10.1126/science.1259530 2014)