We report the semisynthesis of a fluorescent glutamate sensor protein on cell surfaces. Sensor excitation at 547 nm yields a glutamate-dependent emission spectrum between 550 and 700 nm that can be exploited for ratiometric sensing. On cells, the sensor displays a ratiometric change of 1.56. The high sensitivity toward glutamate concentration changes of the sensor and its exclusive extracellular localization make it an attractive tool for glutamate sensing in neurobiology.
James Gonzalo King, Eilif Benjamin Muller, Michael Reimann, Marwan Muhammad Ahmed Abdellah, Giuseppe Chindemi, Pramod Shivaji Kumbhar, András Ecker, Daniela Egas Santander, Ioannis Magkanaris, Sirio Bolaños Puchet, Jorge Blanco Alonso, James Bryden Isbister
Evelyne Ruchti, Brian Donal McCabe