Date of Award

Fall 10-1-2021

Document Type


Degree Name

Doctor of Philosophy (PhD)



First Advisor

Batista, Victor


To oxidize two waters into molecular oxygen, the OEC requires channels via which it can bring in new substrate waters and release protons through PCET as the manganese centers are oxidized. Three water channels surround the OEC: the narrow, broad, and large. Each channel possesses its own unique set of properties that make it ideal for a different purpose. Using network analysis and novel occupancy analysis, the stability of each channel's water positions and hydrogen bond network was quantified, showing the stark differences between the channels. The narrow channel is very sensitive to the oxidation of Mn4, appearing to prepare for the binding of WX to Mn4 during the S2 to S3 transition. The broad channel has a robust network of hydrogen bonded waters that are ideally suited to proton transport, as well as being surrounded by a number of anionic amino acids that could serve as proton rest stops.