When viruses attack our crops they can wipe them out, and in some parts of the world, this can be a death sentence. So naturally, scientists are keen to find a way to provide protection against these infections. Viruses usually attack by using parts of the victim's own cell machinery against it, so in theory, if you can change this component or protein, the virus won't recognise it, and its attack will have been neutralised. But, if you fiddle about with the stuff inside a cell too much, the cell won't be able to use it and will die anyway. Now, a group from the University of Granada in Spain may have a solution, at least for the bacteria E coli, by going back in time billions of years. Georgia Mills spoke to Jose Sanchez-Ruiz to find out more