%0 Journal Article
%A Shibazaki, Chie
%A Shimizu, Rumi
%A Kagotani, Yuji
%A Ostermann, Andreas
%A Schrader, Tobias E.
%A Adachi, Motoyasu
%T Direct Observation of the Protonation States in the Mutant Green Fluorescent Protein
%J The journal of physical chemistry letters
%V 11
%@ 1948-7185
%C Washington, DC
%I ACS
%M FZJ-2020-04412
%P 492-496
%D 2020
%X Neutron crystallography has been used to elucidate the protonationstates for the enhanced green fluorescent protein, which has revolutionized imagingtechnologies. The structure has a deprotonated hydroxyl group in the fluorescentchromophore. Also, the protonation states of His148 and Thr203, as well as theorientation of a critical water molecule in direct contact with the chromophore, couldbe determined. The results demonstrate that the deprotonated hydroxyl group in thechromophore and the nitrogen atom ND1 in His148 are charged negatively andpositively, respectively, forming an ion pair. The position of the two deuterium atomsin the critical water molecule appears to be displaced slightly toward the acceptoroxygen atoms according to their omit maps. This displacement implies the formationof an intriguing electrostatic potential realized inside of the protein. Our findingsprovide new insights into future protein design strategies along with developments inquantum chemical calculations.
%F PUB:(DE-HGF)16
%9 Journal Article
%$ pmid:31880458
%U <Go to ISI:>//WOS:000508473400022
%R 10.1021/acs.jpclett.9b03252
%U https://juser.fz-juelich.de/record/887775