Toward understanding the S2-S3 transition in the Kok cycle of Photosystem II: Lessons from Sr-substituted structure

نویسندگان

چکیده

Understanding the water oxidation mechanism in Photosystem II (PSII) stimulates design of biomimetic artificial systems that can convert solar energy into hydrogen fuel efficiently. The Sr2+-substituted PSII is active but slower than with native Ca2+ containing as an oxygen evolving catalyst. Here, we use Density Functional Theory (DFT) to compare energetics S2 S3 transition Mn4O5Ca2+ and Mn4O5Sr2+ clusters. calculations show deprotonation bound (W3), required for transition, energetically more favorable Mn4O5Sr2+. In addition, have calculated pKa bridges Mn4 Ca2+/Sr2+ state using continuum electrostatics. higher by 4 pH units Mn4O5Sr2+cluster.

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ژورنال

عنوان ژورنال: Inorganic Chemistry Communications

سال: 2021

ISSN: ['1387-7003', '1879-0259']

DOI: https://doi.org/10.1016/j.inoche.2021.108890