Influence of Ligand Complexity on the Spectroscopic Properties of Type 1 Copper Sites: A Theoretical Study
Corresponding Author
Umut Ozuguzel
Department of Chemistry, University of Connecticut, Stamford, Connecticut, USA
Correspondence:
Umut Ozuguzel ([email protected])
Adelia J. A. Aquino ([email protected])
Search for more papers by this authorSerzat Safaltin
Department of Materials Science and Engineering and Institute of Materials Science, University of Connecticut, Storrs, Connecticut, USA
Search for more papers by this authorS. Pamir Alpay
Department of Materials Science and Engineering and Institute of Materials Science, University of Connecticut, Storrs, Connecticut, USA
Department of Physics, University of Connecticut, Storrs, Connecticut, USA
Search for more papers by this authorKenda Alkadry
Department of Chemistry, University of Connecticut, Stamford, Connecticut, USA
Search for more papers by this authorReed Nieman
Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas, USA
Search for more papers by this authorCarol Korzeniewski
Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas, USA
Search for more papers by this authorCorresponding Author
Adelia J. A. Aquino
Department of Mechanical Engineering, Texas Tech University, Lubbock, Texas, USA
Correspondence:
Umut Ozuguzel ([email protected])
Adelia J. A. Aquino ([email protected])
Search for more papers by this authorCorresponding Author
Umut Ozuguzel
Department of Chemistry, University of Connecticut, Stamford, Connecticut, USA
Correspondence:
Umut Ozuguzel ([email protected])
Adelia J. A. Aquino ([email protected])
Search for more papers by this authorSerzat Safaltin
Department of Materials Science and Engineering and Institute of Materials Science, University of Connecticut, Storrs, Connecticut, USA
Search for more papers by this authorS. Pamir Alpay
Department of Materials Science and Engineering and Institute of Materials Science, University of Connecticut, Storrs, Connecticut, USA
Department of Physics, University of Connecticut, Storrs, Connecticut, USA
Search for more papers by this authorKenda Alkadry
Department of Chemistry, University of Connecticut, Stamford, Connecticut, USA
Search for more papers by this authorReed Nieman
Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas, USA
Search for more papers by this authorCarol Korzeniewski
Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas, USA
Search for more papers by this authorCorresponding Author
Adelia J. A. Aquino
Department of Mechanical Engineering, Texas Tech University, Lubbock, Texas, USA
Correspondence:
Umut Ozuguzel ([email protected])
Adelia J. A. Aquino ([email protected])
Search for more papers by this authorFunding: This work was supported by the National Science Foundation (CBET-1922956).
ABSTRACT
Multi-copper oxidases (MCOs) are enzymes of significant interest in biotechnology due to their efficient catalysis of oxygen reduction to water, making them valuable in sustainable energy production and bio-electrochemical applications. This study employs time-dependent density functional theory (TDDFT) to investigate the electronic structure and spectroscopic properties of the Type 1 (T1) copper site in Azurin, which serves as a model for similar sites in MCOs. Four model complexes of varying complexity were derived from the T1 site, including 3 three-coordinate models and 1 four-coordinate model with axial methionine ligation, to explore the impact of molecular branches and axial coordination. Calculations using ωB97X-D3 functional, def2-TZVP basis set, and conductor-like polarizable continuum model (CPCM) solvation model reproduced key experimental spectral features, with increased model complexity improving agreement, particularly for the ~400 cm−1 band splitting in resonance Raman spectra. This work enhances our understanding of T1 copper sites' electronic properties and spectra, bridging the gap between simplified models and complex proteins. The findings contribute to the interpretation of spectroscopic data in blue copper proteins and may inform future studies on similar biological systems.
Open Research
Data Availability Statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.
Supporting Information
| Filename | Description |
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| jcc70013-sup-0001-Supinfo.docxWord 2007 document , 3.4 MB |
Data S1. Supporting Information. |
Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
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