Klaus M Hahn

Klaus Michael Hahn is an American scientist and educator, recognized for his work developing methods to study molecular behavior inside living cells, especially fluorescent biosensors, optogenetics and chemogenetics.

Education and academic career Hahn earned his B.S in biochemistry and philosophy from the University of Pennsylvania, and his Ph.D. in chemistry from the University of Virginia. at the University of North Carolina at Chapel Hill. He was co-founder of the Olympus Imaging Center at UNC, and served on advisory boards for the National Cancer Institute’s Frederick National Laboratory, and was awarded a Transformative R01 Award and the James Shannon Director’s Award from the National Institutes of Health. Nature Reviews Molecular Cell Biology named his work on fluorescent biosensors one of the “ten breakthroughs of the decade”. In 2019 he was awarded the Pearse Prize of the Royal Microscopy Society.

Notable lectures: Pearse Prize Lecture, Royal Microscopy Society, 2019; Leica Scientific Forum France 2012; and environment-sensing dyes. His laboratory has extended biosensor imaging to study conformational changes of single molecules inside living cells. These studies revealed how localized, transient protein activation events, especially of small GTPases, generate cell movement.

More recently, the Hahn lab focused on precisely controlling specific cell components within cells and animals. They showed how proteins can be engineered to respond to light or small molecules, using a variety of generalizable techniques. This was especially valuable for the broad range of proteins that, unlike rhodopsins and channel proteins used earlier, had not evolved to respond to light. By inserting engineered domains into specific cell constituents, they and their collaborators elucidated mechanisms of memory, immune function, cell motility and others.