Additionally, we acknowledge that in a real biological setting, the system would not be fully immersed in an aqueous environment, which is another difference between our current treatment and actual biological conditions. As with the phenol-water complex, we first optimized the geometries of the glutamic acid-glutamate complex in both gas phase and aqueous phase. As shown in by the two residues, 114 although as acknowledged above, there are some differences between the current setup and real biological conditions.