A team of Berkeley Lab researchers conducted X-ray footprinting mass spectrometry (XFMS) experiments at the Lab’s Advanced Light Source (ALS) to pinpoint how a protein of the bacterium Shewanella oneidensis transfers electrons to a metal oxide substrate. The research was led by Caroline Ajo-Franklin, whose lab is part of the Molecular Foundry and who holds a secondary appointment in the Molecular Biophysics and Integrated Bioimaging (MBIB) division, in collaboration with Corie Ralston, also of MBIB. Tatsuya Fukushima, a former postdoc in Ajo-Franklin’s lab, and Sayan Gupta, a member of Ralston’s lab, were co-first authors on the paper published in the Journal of the American Chemical Society. The study, which identified an unexpectedly small and weak binding site, also benefitted from expertise and tools contributed by Joint BioEnergy Institute (JBEI) and Biological Systems and Engineering (BSE) researchers Christopher Petzold and Leanne Jade Chan. Read more at the Berkeley Lab News Center. This work has also been profiled in an ALS Science Highlight.