EuroBIC-17 OL85 Repurposing a Miniaturized Electron Transfer Protein by Metal Replacement M. Chino*, L. Leone, S. La Gatta, L. Di Costanzo, F. Arrigoni, D. Aref, and A. Lombardi Department of Chemical Sciences, University of Naples “Federico II”, Via Cintia, 80126, Napoli, Italy [email protected]  As bioinorganic chemists, our curiosity propels us beyond the boundaries explored by evolution in nature thus far. We may distinguish three distinct levels to modulate metal sites in proteins:[1] (i) substitution of the metal center, (ii) chemical modification of both endogenous and exogenous ligands and/or the cofactor (e.g., various heme types, pyranopterin-dithiolate), and (iii) the covalent and noncovalent array of interactions in the second coordination sphere. We recently reported the design of a single-chain linear protein, METPsc, capable of meeting all the prerequisites for folding and functioning akin to a natural Rubredoxin (Rd, FeCys4 site) within only 28 residues.[2] A deliberately elevated reduction potential was engineered for the Fe(III)/Fe(II) pair, and its efficacy in electron transfer was validated in a photo-triggered electron transfer process. In this work, we broaden the application range of our designed scaffold through the adoption of the first modulation strategy, metal ion substitution. We demonstrate that, analogous to natural Rds,[3-4] METPsc can accommodate various metal ions, including Co, Cd, and Mo. Each interaction offers valuable insights into the reciprocal influence exerted by the metal on the protein ligand and vice versa, facilitated by a combination of crystallography, spectroscopy, calorimetry, and computational methods.

[1] L. Leone, M. Chino, F. Nastri, O. Maglio, V. Pavone, A. Lombardi, Biotechnol. and Appl. Biochem. 2020, 67, 495–515.  [2] M. Chino, L. F. Di Costanzo, L. Leone, S. La Gatta, A. Famulari, M. Chiesa, A. Lombardi, V. Pavone, Nat. Commun. 2023, 14, 2368. [3] B. K. Maiti, R. M. Almeida, I. Moura, J. J. G. Moura, Coord. Chem. Rev. 2017, 352, 379–397. [4] J. W. Slater, S. C. Marguet, M. E. Gray, H. A. Monaco, M. Sotomayor, H. S. Shafaat, ACS Catal. 2019, 9, 89288942. 

Conference Title

17th European Biological Inorganic Chemistry Conference (EuroBIC-17)

Conference Country

United Kingdom

Conference Date

Aug. 25, 2024 - Aug. 29, 2024

Conference Sponsor

University of Münster