DNA is a complex biological structure that contains the instructions for an organism to develop, live, and reproduce. Although it is very resilient, it's not inert and can be damaged by both external and internal metabolic processes. One common type of damage, methylation of DNA nitrogenous bases, helps regulate genes but is also connected to disease and ageing.
The methylation process changes the structure of the DNA, which then influences the electron transfer process that is important for cell signalling. But the mechanism behind this interplay between structure and electron transport at the microscopic level isn't known.
Working with collaborators in Malaysia, RIKEN in Japan, and ISIS, Wan Nurfadhilah Zaharim from the Department of Chemical Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia uses a combination of experimental and computational techniques to study the electronic structure and electron transfer in DNA, as well as the effects of modifications.
They regularly visit ISIS for experiments because muon spectroscopy is a crucial tool in their work. Muons act as probes, giving information that is important in interpreting how electrons diffuse in a DNA molecule. Alongside muon spectroscopy, they have used scanning tunnelling microscopy and transmission electron microscopy, as well as computational techniques.
In their current work, they are comparing normal and methylated DNA to quantify the effect of the modification on the electron transport.
As well as providing answers to long-standing questions about DNA, their work is also relevant to biosensors where electron transfer to DNA is relevant.
During their most recent visit to ISIS, Wan Nur Aini Wan Mokhtar, also from the Department of Chemical Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, joined for her first muon experiment. “It was an amazing experience, “she said. “It's not just because of the science, but also because I had the chance to meet brilliant scientists and collaborators who made the experience so inspiring and welcoming."
