(Phys.org)—A team of researchers at Stanford University has used ultrafast x-ray absorption and emission spectroscopy to quantify the entatic state of cytochrome c. In their paper published in the journal Science, the group outlines their procedure and what they learned. Kara Bren and Emma Raven with the University of Rochester and University of Leicester respectively offer a Perspective piece on the work done by the team in the same journal issue, and outline some of the implications regarding the role that the protein plays in cell life and death.